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Asia Pacific
Physics Newsletter
May 2016
Volume 5 • Number 2
worldscinet.com/appn
Legend of Abdus Salam
1979 Nobel Laureate in Physics
published by
Institute of Advanced Studies, Nanyang Technological University (IAS@NTU)
and South East Asia Theoretical Physics Association (SEATPA)
South East Asia Theoretical Physics Association
Institute of Advanced Studies
Institute of Advanced Studies @ Nanyang Technological University
– Institute of Physics UK Joint Workshop on Physics Education
Envisioning Physics
Education for the
21st Century
5 to 6 September 2016
Nanyang Executive Centre, NTU
CO-CHAIRS
SPEAKERS
Kok-Khoo Phua
Director, Institute of Advanced Studies, NTU
Tajamal Bhutta Institute of Physics UK
Paul Hardaker Institute of Physics UK
Leong Chuan Kwek Institute of Advanced Studies, NTU
Choy Heng Lai Yale-NUS College
Hock Lim National University of Singapore
Becky Parker Institute for Research in Schools (to be confirmed)
Chorng Haur Sow Institute of Physics Singapore
Charles Tracy Institute of Physics UK
Mary Whitehouse University of York
Gary Williams Institute of Physics UK (to be confirmed)
Proty Wu Jiun-Huei National Taiwan University
and many others
Paul Hardaker
Chief Executive, Institute of Physics UK
www.ntu.edu.sg/ias
For enquiries, please email [email protected]
Supporting Organisations
School of Physical and Mathematical Sciences
Asia Pacific
Physics Newsletter
May 2016 • Volume 5 • Number 2
Asia Pacific Physics Newsletter publishes
articles reporting frontier discoveries in
physics, research highlights, and news
to facilitate interaction, collaboration and
cooperation among physicists in Asia
Pacific physics community.
Editor-in-Chief
Kok Khoo Phua
A publication of the IAS@NTU Singapore and SEATPA
3
4
Swee Cheng Lim
14
PEOPLE
Elucidating the Quantum Structures in Physics
— Interview with Nobel Laureate Prof Gerard 't Hooft
Prof David Gross's 75th Birthday Conference in Jerusalem
Editorial Team
Unpublished C. N. Yang Interview on Teaching and Research
in Physics
Sen Mu
Chi Xiong
Hui Sun
Erin Ong
Ling Zhang
Memorial Meeting for Nobel Laureate Prof Abdus Salam's
90th Birthday
Salam's Dream and Dynamic Changes in Chinese Condensed
Physics — A Personal Perspective
SEATPA Committee
Graphic Designers
COVER STORY
Abdus Salam at Imperial College London
Associate Editor-in-Chief
Christopher C Bernido
Phil Chan
Leong Chuan Kwek
Choy Heng Lai
Swee Cheng Lim
Ren Bao Liu
Hwee Boon Low
Anh Ký Nguyên
Choo Hiap Oh
Kok Khoo Phua
Roh Suan Tung
Preecha Yupapin
Hishamuddin Zainuddin
Freddy Zen
EDITORIAL
31
ARTICLES
Superconductivity in a Terrestrial Liquid: What Would It Be
Like?
Einstein versus the Physical Review
Reflections on the Discovery of Einstein's Gravitational Waves
42
NEWS
Recent News from the Overseas Chinese Physics Association
International Workshop on "Fundamental Science and
Society" in Vietnam: Celebration of the 50th Anniversary of the
"Rencontres de Moriond"
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OBITUARY
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EDITORIAL
Featured in this May issue of the Asia Pacific Physics Newsletter is the Memorial Meeting for
Nobel Laureate Abdus Salam’s 90th Birthday which was held in Singapore this January. The late
Abdus Salam was the first Muslim to win the Nobel Prize in Science in 1979. He was the Founding
Director of International Centre for Theoretical Physics (ICTP) in Trieste, Italy and the Founding
President of the Third World Academy of Sciences. Prof Michael Duff (FRS) from Imperial College
London shared his personal reminiscences of the legacy of Abdus Salam at Imperial College
London. Prof Yu Lu of the Institute of Physics, Chinese Academy of Sciences who spent about
20 years as Head of Condensed Matter Physics at ICTP gave a personal perspective of Salam's
dream and dynamic changes in Chinese condensed matter physics.
Nobel Laureate Prof Gerard 't Hooft attended the Memorial Meeting and he shared with us his
views on elucidating the quantum structures through an insightful interview. An interesting
unpublished interview with Nobel Laureate Prof C N Yang on his teaching and research experience in Physics is also featured. Another highlight is the celebration of Nobel Laureate Prof
David Gross' 75th Birthday Conference in Jerusalem. Turing Prize Winner Prof Andrew Yao
explored the development of quantum computing in his talk at the HKUST 25th Anniversary
Distinguished Speaker Series.
Editor in Chief
Kok Khoo Phua
President, South East Asia Theoretical Physics Association
Director, Institute of Advanced Studies, Nanyang Technological University
May 2016, Volume 5 No 2
3
COVER STORY
Memorial Meeting for
Nobel Laureate
Prof Abdus Salam’s
90th Birthday
Lars Brink
Chalmers Institute of Technology
O
n 29 January 2016, Nobel Laureate Abdus Salam
would have been 90. Unfortunately he passed away
far too young almost twenty years ago. Abdus Salam
rose from modest conditions in the little village Jhang in what
would become Pakistan to become one of the most important
scientists of the last century. After having broken all school
records even writing a paper in mathematics, he came to
Cambridge to get his PhD in 1951. In 1957, he was called to
Imperial College in London as Professor and there he built
up a world leading group in theoretical physics. At the young
age of just 33, he was elected a Fellow of the Royal Society.
From the beginning, he had a burning interest to help
the third world to establish basic science and in 1964, he
managed to establish a dream of his: the International Centre
for Theoretical Physics (ICTP) in Trieste, where over the fifty
years that it has existed, thousands of young scientists from
developing countries have been trained and matured. One
cannot overemphasize the importance of ICTP, now properly
Co-Chair Prof Michael Duff (Imperial College London) gave a warm
welcome to the participants of the conference.
Nobel Laureate Prof Gerard 't Hooft (Universiteit Utrecht) discussed the
Standard Model in his talk.
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Asia Pacific Physics Newsletter
COVER STORY
Speakers and participants posing for a memorable group photograph.
called The Abdus Salam International Centre for Theoretical
Physics. With boundless energy, he travelled the world to
speak about the importance of science and in his home
country, he set up all the necessary research infrastructure,
organizing among other things Pakistan's Atomic Energy
Commission.
Abdus Salam's contributions to physics are huge. In his
thesis, he finalized the proof of renormalization of QED. He
later introduced the two-component nature of the neutrino
and during the 1960s, he developed gauge theory as the
correct framework for the electro-weak theory, a work
for which he shared the Nobel Prize in 1979 with Sheldon
Glashow and Steven Weinberg. He was one of the first to
understand the importance of supersymmetry and with
Strathdee, he introduced the superfields. Even with his
heavy international workload, he was always on top of what
happened in particle physics. A proof of his standing is the
44 honorary doctorates that he earned.
A conference to the memory of his 90th birthday was held
at the Institute of Advanced Studies, Nanyang Technological
University (NTU) in Singapore from 25 to 28 January 2016.
Many of his collaborators, students and friends came to
give lectures. Four Nobel laureates, David Gross, Tony
Leggett, Carlo Rubbia, and Gerard 't Hooft, participated
as well as many other famous physicists. The talks were
partly historical. Michael Duff talked about Abdus Salam
and his life, career and many of his old collaborators, such
as Jogesh Pati, Robert Delbourgo and Yu Lu, interfoliated
their scientific talks with reminiscences. Many of Salam's
old students gave talks about their present works, such as
Peter West, Ali Chamseddine and Qaisar Shafi. One day
was devoted to the present situation of particle physics
with talks by Peter Jenni, Jim Virdee, Carlo Rubbia, David
Gross and Hirotaka Sugawara. ICTP was well represented
with talks by the present director Fernando Quevedo, and
his predecessor, Miguel Virasoro. Around 120 participants
took part in the conference that was held in the Nanyang
Executive Centre at NTU.
For more information about the memorial meeting, visit
http://www.ntu.edu.sg/ias/upcomingevents/MMAS/Pages/
default.aspx
The proceedings cum the memorial book of Abdus Salam
will be published by World Scientific.
May 2016, Volume 5 No 2
5
COVER STORY
Mr Ahmad Salam, son of Professor Abdus Salam, giving a speech at the conference banquet, held at Pan Pacific Hotel, Singapore.
Speakers list for the Memorial Meeting for Nobel Laureate
Prof Abdus Salam's 90th Birthday:
- Ahmad Salam
(Son of Prof Abdus Salam)
- Ahmed Ali
The Deutsches Elektronen-Synchrotron (DESY)
- Francis Allotey
African Institute Of Mathematical Sciences
- Eric Bergshoeff
University of Groningen
- Lars Brink
Chalmers Institute of Technology
- Ali Chamseddine
American University of Beirut
- Pisin Chen
National Taiwan University
- Robert Delbourgo
University of Tasmania
- Michael Duff
Imperial College London
- Sergio Ferrara
CERN
- Harald Fritzsch
Ludwig Maximilians University
- Christian Fronsdal
University of California, Los Angeles
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Asia Pacific Physics Newsletter
- Kazuo Fujikawa
RIKEN
- David Gross
University of California, Santa Barbara
- Chris Hull
Imperial College London
- Tasneem Zehra Husain
Theoretical physicist and writer
- Peter Jenni
CERN
- Anthony Leggett
University of Illinois at Urbana-Champaign
- Madumbai S. Narasimhan
Indian Institute of Science
- Jordan Nash
Imperial College London
- Jogesh Pati
SLAC, Stanford University
- Fernando Quevedo
International Centre for Theoretical Physics (ICTP)
- Eliezer Rabinovici
The Hebrew University of Jerusalem
- Muneer Rashid (contributed speaker)
National University of Science and Technology
- Carlo Rubbia
CERN
- Stefano Ruffo
International School for Advanced Studies (SISSA)
COVER STORY
Chaired by Prof Lars Brink (fourth from right), the panel discussion on "The Future of Fundamental Physics" included seven prominent scientists, (from
left) Profs Pisin Chen (National Taiwan University), Peter Jenni (CERN), Gerard 't Hooft (Universiteit Utrecht), David Gross (University of California,
Santa Barbara), Carlo Rubbia (CERN), Tejinder Virdee (Imperial College London) and Hirotaka Sugawara (Okinawa Institute of Science and Technology).
- Qaisar Shafi
University of Delaware
- Kellogg Stelle
Imperial College London
- Hirotaka Sugawara
Okinawa Institute of Science and Technology
- Gerard 't Hooft
Universiteit Utrecht
- George Thompson
International Centre for Theoretical Physics (ICTP)
- Miguel Virasoro
National University of General Sarmiento
- Jim Virdee
Imperial College London
- Spenta Wadia
Tata Institute of Fundamental Research
- Peter West
King's College London
- Lu Yu
The Chinese Academy of Sciences (CAS)
- Arnulfo Zepeda (contributed speaker)
The Center for Research and Advanced Studies of the
National Polytechnic Institute (Cinvestav)
May 2016, Volume 5 No 2
7
COVER STORY
Abdus Salam at
Imperial College London
Michael James Duff
Imperial College London
Some personal reminiscences of the legacy of Abdus
Salam at Imperial College London, by a former
graduate student, delivered at the Memorial Meeting
for Nobel Laureate Prof Abdus Salam's 90th Birthday,
IAS/NTU Singapore 23-28 January 2016.
T
he death of Abdus Salam in 1996 was a great loss not
only for his family and the scientific community;
it was a loss to all mankind. For he was not only
one of the finest physicists of the twentieth century, having
unified two of the four fundamental forces of nature, but he
dedicated his life to the betterment of science and education
in the developing world. So although he won the Nobel Prize
for Physics, a Nobel Peace Prize would have been equally
appropriate.
Salam was born in Jhang, in what is now Pakistan, in
1926, and came from what he himself described as humble
beginnings. In fact, “I am a humble man” was something
of a catchphrase for Salam, used whenever anyone tried
to make physics explanations more complicated than
necessary. He attended the Government College in Lahore
and Panjab University before setting off for England and
St. John's College, Cambridge, in 1946 where he gained a
double first in Physics and Mathematics. He gained his PhD
at the Cavendish Laboratory in 1952. He returned to Lahore
for a few years but was appointed lecturer at Cambridge
University in 1954.
Undoubtedly, the greatest influence on Salam at these
early stages of his career was his mentor at St. John's, the
great Paul Dirac, who remained Salam's hero throughout his
life both as a great physicist and as a man who was largely
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Asia Pacific Physics Newsletter
When all else fails,
you can always tell
the truth.
Abdus Salam
disinterested in material wealth. Likewise, Salam himself
never craved riches, and was known to have paid for poor
Third World students and postdoctoral researchers out of
his own pocket.
Among Salam's earlier achievements was the role played
by renormalisation in quantum field theory when, in
particular, he amazed his Cambridge contemporaries with
his resolution of the notoriously thorny problem of overlapping divergences. His brilliance then burst on the scene
once more when he proposed the famous hypothesis that
All neutrinos are left-handed, a hypothesis which inevitably
called for a violation of parity in the weak interactions. He
was fond of recalling the occasion when he submitted (I
should say “humbly”) his two-component neutrino idea to
the formidable Wolfgang Pauli, whose verdict was: “Give
my regards to my friend Salam and tell him to work on
something better”, adding that “this young man does not
realize the sanctity of parity!”. As a result, Salam delayed
publication until after Lee and Yang had conferred the mantle
of respectability on parity violation. This experience taught
Salam a valuable lesson and he would constantly advise his
students never to listen to grand old men (I hope this student,
at least, has lived up to that advice!). It also taught him to
adopt a policy of publish or perish, and his scientific output,
with over 300 publications, was prodigious.
COVER STORY
The Theoretical Physics group at Imperial College was
founded in 1957 when the then-Head of Physics, Lord Patrick
Blackett, persuaded Abdus Salam to leave Cambridge and
come to Imperial, notwithstanding attempts by his superiors
at Cambridge to retain him. Salam remained Professor of
Theoretical Physics until his death in 1996. At the early age
of 33, he was elected to a Fellowship of the Royal Society in
1959. In 2007, the anniversary of Salam’s arrival at Imperial
was celebrated with the ‘’Salam+50’’ conference.
His work at Imperial included:
• Spontaneous symmetry breaking with Goldstone and Weinberg.
• Unitary symmetries with Matthews.
• Weak interactions with Ward.
• Symmetry breaking with Kibble.
• Electroweak unification.
Of course, this was the work that won him the 1979
Nobel Prize which he shared with Glashow and Weinberg,
combining several of his abiding interests: renormalisability,
non-abelian gauge theories and chirality. His earlier work
with Goldstone, Weinberg, Matthews, Ward and Kibble was
no doubt also influential.
• Quantum Gravity with Delbourgo, Isham and
Strathdee.
• Grand Unification
Together with Pati, Salam went on to propose that the
strong nuclear force might also be included in this unification. Among the predictions of this Grand Unified Theory
are magnetic monopoles and proton decay: phenomena
which are still under intense theoretical and experimental
investigation.
• Supersymmetry and superspace with Strathdee.
More recently, it was Salam, together with his lifelong
collaborator John Strathdee who first proposed the idea of
superspace, a space with both commuting and anticommuting coordinates, which underlies much of present day
research on supersymmetry.
My personal involvements with Salam were:
• I was fortunate enough to be his PhD student
from 1969 to 1972.
Regrettably, no-one suggested that weak interaction
physics would be an interesting topic of research. In fact
I did not learn about spontaneous symmetry breaking
until after I received my PhD. The reason, of course, is that
neither Weinberg nor Salam (nor anyone else) fully realized the importance of their model until t'Hooft proved its
renormalisability in 1972 and until the discovery of neutral
currents at CERN. Indeed, in 1979, the Nobel Committee
May 2016, Volume 5 No 2
9
COVER STORY
men's room, so that was frequently the location for receiving
your new orders.
• First postdoctoral appointment in Trieste
1972-1972
• Faculty colleague in the Theoretical Physics
Group 1979-1988
• Abdus Salam Professor of Theoretical Physics,
2005-2015
were uncharacteristically prescient in awarding the Prize
to Glashow, Weinberg and Salam, as it was not until 1982
that the W and Z bosons were discovered experimentally
at CERN.
However, it is to Abdus Salam as the man who first
kindled my interest in the Quantum Theory of Gravity (a
subject which at the time was pursued only by mad dogs and
Englishmen) that I owe a tremendous debt. My thesis title:
Problems in the Classical and Quantum Theories of Gravitation was greeted with hoots of derision when I announced it
at the Cargese Summer School en route to my first postdoctoral appointment in Trieste. The work originated in a bet
between Abdus Salam and Hermann Bondi about whether
one could describe black holes using Feynman diagrams.
Based on my calculations Salam claimed victory but I never
found out if Bondi ever paid up. It was inevitable that Salam
would not rest until the fourth and most enigmatic force of
gravity was unified with the other three. Such a unification
had always been Einstein's dream and it remains among
the most challenging tasks in modern theoretical physics
and one which attracts the most able and active researchers.
Being a student of someone so bursting with new ideas as
Salam was something of a mixed blessing: he would allocate a
research problem, and then disappear on his travels for weeks
at a time (consequently, it was to Christopher Isham that I
would turn for practical help with my PhD thesis). On his
return he would ask what you were working on. When you
began to explain your meagre progress he would usually say
“No, no, no. That's all old hat. What you should be working
on is this”, and he would then allocate a completely new
problem! After a while, students began to wise up and would
try to avoid him until we had achieved something concrete.
Of course, the one place that could not be avoided was the
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Asia Pacific Physics Newsletter
These scientific achievements reflect only one side of
Salam's character. He also devoted his life to the goal of
international peace and cooperation, especially to the gap
between the developed and developing nations. He firmly
believed that this disparity would never be remedied until
Third World countries become arbiters of their own scientific and technological destinies. This means going beyond
mere financial aid and the export of technology; it means
the training of a scientific elite capable of discrimination in
all matters scientific. He would thus vigorously defend the
teaching of esoteric subjects such as theoretical elementary
particle physics against critics who complained that the
time and effort would be better spent on agriculture. His
establishment of the International Centre for Theoretical
Physics (ICTP) in Trieste was an important first step in
this direction. He served as President of the Third World
Academy of Sciences, and was hotly tipped as the Director
of UNESCO until ill-health forced him to withdraw his
candidacy. He also acted as chief scientific advisor to the
President of Pakistan. His visionary insights into the urgent
need for science and technology in the Third World are set
out in his book Ideals and Realities.
I will not list his numerous awards but must mention the
Atoms for Peace Prize (1968), the Einstein Medal (1979) and
the Peace medal (1981). He holds honorary degrees from
over 40 universities worldwide and received a Knighthood
for services to British Science in 1989.
Another aspect of Salam's thinking was that he remained
a devout Muslim all his life. Unfortunately, this is the side of
his character on which I am the least qualified to comment,
except to say that he took it all very seriously. On a lighter
note, the evening of the Nobel ceremony was memorable
in that Salam arrived attired in traditional dress: bejewelled
turban, baggy trousers, scimitar and those wonderful curly
shoes that made him appear as though he had just stepped
out of the pages of the Arabian Nights. The net result, of
course, was that he completely upstaged Glashow and
Weinberg (which I suspect may not have displeased him!).
It is indeed a tragedy that one as vigorous and full of life
COVER STORY
as Abdus Salam should have been struck down with such a
debilitating disease. He had such a wonderful joie de vivre
and his laughter, which most resembled a barking sea-lion,
would reverberate throughout the corridors of the Imperial
College Theory Group. When the deeds of great men are
recalled, one often hears the cliche “He did not suffer fools
gladly”, but my memories of Salam at Imperial College were
quite the reverse. People from all over the world would arrive
and knock on his door to expound their latest theories, some
of them quite bizarre. Yet Salam would treat them all with
the same courtesy and respect. Perhaps it was because his
own ideas always bordered on the outlandish that he was so
tolerant of eccentricity in others; he could recognise pearls
of wisdom where the rest of us saw only irritating grains
of sand. One such was the young military attaché from the
Israeli embassy in London who showed up one day with his
ideas on particle physics. Salam was impressed enough to
take him under his wing. The young man was Yuval Ne'eman
and the result was flavor SU(3).
Let me recall just one example of a crazy Salam idea.
In that period 1969-72, one of the hottest topics was
the Veneziano Model and I distinctly remember Salam
remarking on the apparent similarity between the mass and
angular momentum relation of a Regge trajectory and that of
an extreme black hole. Nowadays, of course, string theorists
will juxtapose black holes and Regge slopes without batting
an eyelid but to suggest that black holes could behave as
elementary particles back in the late 1960s was considered
preposterous by lesser minds. As an interesting historical
footnote, let us recall that at the time, Salam had to change
the gravitational constant to match the hadronic scale, an
idea which spawned his strong gravity; today the fashion
is the reverse and we change the Regge slope to match the
Planck scale!
Theoretical physicists are, by and large, an honest bunch:
occasions when scientific facts are actually deliberately
falsified are almost unheard of. Nevertheless, we are still
human and consequently want to present our results in the
best possible light when writing them up for publication. I
recall a young student approaching Abdus Salam for advice
on this ethical dilemma: “Professor Salam, these calculations
confirm most of the arguments I have been making so far.
Unfortunately, there are also these other calculations which
do not quite seem to fit the picture. Should I also draw the
reader's attention to these at the risk of spoiling the effect
or should I wait? After all, they will probably turn out to be
irrelevant.”. In a response which should be immortalized in
The Oxford Dictionary of Quotations, Salam replied: “When
all else fails, you can always tell the truth.”.
As Robert Walgate remarked in the New Scientist in 1976,
“Salam is a cultural amphibian. He has the heart of a poet and
the mind of a scientist. He is an excellent physicist concerned
with deep patterns; he is also a deeply compassionate man.
These two threads intertwined throughout his life.”.
I think it was Hans Bethe who said that there are two
kinds of genius. The first group (to which I would say
Steven Weinberg, for example, belongs) produce results
of such devastating logic and clarity that they leave you
feeling that you could have done that too (if only you were
smart enough!). The second kind are the “magicians” whose
sources of inspiration are completely baffling. Salam, I
believe, belonged to this magic circle and there was always
an element of Eastern mysticism in his ideas that left you
wondering how to fathom his genius.
Acknowledgments:
I am grateful to my conference co-organizers K.K. Phua and
Lars Brink for affording me this opportunity to pay homage
to Abdus Salam.
May 2016, Volume 5 No 2
11
COVER STORY
Salam’s Dream and Dynamic
Changes in Chinese
Condensed Matter Physics
— A personal perspective
Lu Yu
Institute of Physics, Chinese Academy of Sciences
P
rofessor Abdus Salam deeply believed that ‘scientific
thought is the common heritage of all mankind’
and had the dream that the developing world could
contribute equally to that heritage. I was fortunate to work
directly under his supervision for 10 years at the International Centre for Theoretical Physics (ICTP) in Trieste, Italy,
founded and directed by him. I could witness personally how
he devoted his wisdom, energy, heart and soul to materialize
this dream for the developing word. I could also witness how
his dream was coming true, at least partially, in some parts
of the South, including China, although the path was not
straightforward, full of challenges and difficulties.
A half-century ago, modern condensed matter physics
was almost nonexistent in China. However, during the
past 30 years, especially since the beginning of the 21st
century, the situation has changed dramatically. A number
of outstanding young physicists from China with cutting
edge research achievements now have global recognition.
How did this quantal transition occur?
In the late 50s and early 60s about 8000 young Chinese
scientists were trained in the former Soviet Union (SU) for
the Diploma or PhD. degrees. I was fortunate to be one of
them and was appointed a group leader at the Institute of
Physics (IoP), Chinese Academy of Sciences, after returning,
even though I did not have a PhD. The lack of experience
and scientific exchange was partially made up by intensive
self- and mutual- education. A group of almost starving
young people passionately studied and disputed the latest
results in the literature (fortunately, scientific journals were
available at IoP). Under that encouraging environment I
12
Asia Pacific Physics Newsletter
started my own research work and could make a prediction
of the bound states inside the energy gap of superconductors
doped with magnetic impurities. I am very pleased that
the ‘big exercise’ made in the early years of my career still
remains pertinent for the current hunting of the Majorana
fermions, anticipated at the interface of superconductors
and topological insulators.
Unfortunately, that joyful time did not last long. In 1966
the ‘Cultural Revolution’ broke out in China, and normal
research/education activities were almost completely
stopped. In 1969, I was sent to the countryside to do manual
labor, to be ‘re-educated’ by farmers. Research work was out
of the question under those conditions.
Nevertheless, something magical happened after I
returned from the countryside in 1971. Following the
Prof Lu Yu at the "Memorial Meeting for Nobel Laureate Prof Abdus Salam's
90th Birthday" held in January 2016 at Nanyang Technological University.
COVER STORY
‘Ping-Pong’ diplomacy (exchange of table-tennis players
between the US and China) and Richard Nixon’s visit, the
atmosphere in China changed a bit. We could get some information on the breakthrough in the study of phase transitions
and critical phenomena. Again, through uneasy efforts of
intensive self- and mutual-education, we could catch up the
latest developments, performed some sophisticated calculations of the critical exponents and showed those results to
members of the American delegation of Solid State Physics,
who came to visit China in 1975.
The scientific exchange during the ‘Cultural Revolution’ was rather limited, but it was crucial for our scientific
survival and for research continuity. The personal contacts
established then were extremely helpful for recovering our
scientific career and building-up successful international
collaboration after China’s opening up to the outside world.
I was invited by Abdus Salam and Stig Lundqvist
from Sweden to join the ICTP staff in 1986, with a heavyweighted letter from Abdus Salam saying: ‘We would like the
Condensed Matter activities in developing countries to be
enhanced through your presence here at the Centre.’ … ‘We
all look forward to a second revolution in condensed matter
activity in developing countries with your appointment and
through your influence.’ One can imagine how much pressure
and drive was there for me from this kind of anticipation.
The ICTP and its sister organization, the International
School for Advanced Studies (SISSA), have played a tremendous role in promoting science and education in developing
countries, especially after China suffered badly from isolation
and destructions during the ‘Cultural Revolution’. Thousands
of young Chinese scientists visited ICTP-SISSA as postdocs,
trainees in the Italian laboratories, associate members,
participants of schools/conferences, and many of them used
it as a stepping stone to the broad international arena. During
my tenure at ICTP (lasting almost 17 years), I did my best,
under Salam’s supervision and following his advice, and that
token contribution was well recognized by international
colleagues. I was awarded the 2007 AIP (American Institute
of Physics) John T. Tate Medal for International Leadership
in Physics, established for non-Americans. Abdus Salam also
received the same award earlier, in 1978. I felt greatly honored
and pleased, as I was trying very hard to follow his steps.
In 2002 I returned back to China after retirement from
ICTP. Instead of enjoying a relaxed pensioner’s life, I have
still been actively involved in research related activities.
However, my role changed dramatically: no longer as a
research leader or a science organizer, but rather as a senior
adviser, a friend for researchers of different age groups, and
a ‘cheerleader’. In that position I personally witnessed the
dramatic changes in Chinese science, and in condensed
matter physics, in particular.
At the end of February 2008, I was invited by Nanlin
Wang at IoP to join their group meeting, where the latest
report (in Japanese) of Hosono group’s discovery of 26K
iron pnictide superconductors was discussed. In less than a
week, the first paper written by Wang’s group appeared in
arXiv, giving rise to the wave of research on iron-based high
temperature superconductivity worldwide. Soon afterwards
several Chinese groups followed up, pushing the superconducting temperature to the highest record, as commented
in Science, ‘New superconductors propel Chinese physicists
to the forefront’.
This was one of the recent examples. Similar situation was repeated in the studies of topological insulators,
the quantized anomalous Hall effect, as well as the Weyl
fermions/Weyl semi-metals. In fact, among the Top 10
Breakthroughs in 2015, selected by Physics World of the
European Physical Society, two were from China, the leading
breakthrough ‘Double quantum teleportation milestone
in Physics’ by Jianwei Pan’s team and the Weyl fermions. I
know well the research team on Weyl fermions: theoreticians
made precise prediction in which materials these fermions
should be looked for, the material scientists synthesized
these compounds after many unsuccessful attempts, while
the experimentalists measured the photoemission spectra
to confirm the anticipated physical properties on the most
advanced facilities. Theory--material synthesis--characterization, three-in-one, in close, organic collaboration -- a new
productive paradigm appeared.
Surely, these tremendous changes did not come out of
blue: strong government support (the budget of National
Science Foundation (NSF) of China has been increasing by
10-15% annually for the last 10-15 years, the R&D budget
was beyond 2% of GDP in 2014), the large inflow of welltrained scientists (more than 5000 for the last 10 years), the
substantial improvement in research facilities, the consolidation of the research community, and fruitful international
collaborations are the key prerequisites for materializing the
quantal transition.
Abdus Salam said in 1985, at the inauguration conference of the Third World Academy of Sciences (TWAS), a
partner organization of ICTP, also created by him,: ‘…young
men and women from the Third World …enviously, and
deservedly, long to participate in this exciting adventure
of scientific creation on equal terms.’ I would like to report
to Professor Salam that his dream is being materialized, at
least partially, now!
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Elucidating the Quantum
Structures in Physics
— Interview with Nobel Laureate
Prof Gerard ’t Hooft
Yuyang Cai & Chi Xiong
Nanyang Technological University, Singapore
Professor Gerard ’t Hooft is a Dutch theoretical physicist at Utrecht University, the
Netherlands and the 1999 Nobel Prize Laureate in Physics. He has made many important
contributions on gauge theories in particle physics, quantum gravity and black holes
and fundamental questions in quantum mechanics. Besides the Nobel Prize shared with
Martinus Veltman for “elucidating the quantum structure of electroweak interaction in
physics”, he was awarded many notable awards including Heineman Prize (1979), Wolf
Prize (1981), Lorentz Medal (1986), Spinoza Prize (1995), Franklin Medal (1995) and
Lomonosov Gold Medal (2010). He is a member of the Royal Netherlands Academy of
Arts and Science since 1982 and a foreign member of other science academies such as the
French Academy of Sciences, the American National Academy of Sciences and American
Academy of Arts and Sciences and The Britain and Ireland based Institute of Physics.
You are a theoretical physicist. What intrigues you about
this field in the first place?
When I was a child, I was very interested in natural
phenomena, in physics and mathematics – beginning with
numbers. Part of this was also due to my family background.
My grandfather was a well-known zoologist. My grand uncle
was a Nobel Laureate in physics. My uncle, whom I was
very close with at the time, was a highly respected physicist
in Netherlands. So I could ask him all my questions. The
more he tried to answer by saying, “You are too young. You
have to go to the university” – the more eager I was to learn
what it was all about. I was always interested in fundamental
questions – how the laws of nature really work, what we can
do to understand them, what we can do to build nice gadgets.
Radios, satellites, and space travel, all these things have now
become possible. Of course, physics is a major ingredient of
these inventions. From early on, I knew I wanted to learn
about the basic stuff, to understand what was really going on.
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Considering the influence that your family had on you,
would you encourage your own children to continue
this course?
Yes, but only if they really feel attracted to this kind of science,
which is always a combination of environmental factors, with
a little genetic ingredient, I guess. I knew before I could talk
that I wanted to understand the physical world. I started to
talk quite late, not until I was 3. My parents were worried
about this. My grandmother was always encouraging me. She
liked the idea of being busy with your mind, being different
from others, being absorbed into something. It doesn’t have
to be physics - her husband was a zoologist; her other brother
was a chemist. There was a lot of academic activity in the
family. I have two daughters. Of course I wanted to talk to
them about physics, but they were not really interested. One
of my daughters once said that a physicist is someone who
sits there with a blank piece of paper, not talking to anybody
and staring for two hours at the blank paper – that was me
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of course. Before I do a calculation, I need to have clearly in
my mind what I want to understand. I told them that what
I wanted them do to is to search for themselves what is it
that they are really interested in, and in what way they could
be special. You don’t want to be just like all the others. You
want to have some specialty that’s ‘your thing’, your subject,
and you want to be good at it. This worked out well for both
of them, but they didn’t go into physics.
You set out to be a ‘man who knows everything’ as a child.
Do you think you have reached there?
Yes and no. Of course the whole topic of science is much
too large. In the Stone Age, it may have been a good start
for someone to say he wants to understand everything as
much as possible. But we are no longer in the Stone Age.
There are thousands of scientists, specializing in all different
topics - that is the body of science. I did not only want to
become part of it, I wanted to make my own discoveries. In
that respect, I think I have been fairly successful. I did find
new features of the physical world. Also there are things that
I’m not really being credited for, in the sense that people and
the community at large have other opinions about what is the
best approach than my personal ideas. Still, I think personally
I’ve found several things, features that help to understand the
world of very tiny particles, the universe and the forces there.
I partly succeeded, but I cannot say that I know everything
at all. There is very much to be known.
What goals do you have at this stage of life?
I know that I’m no longer as productive as I used to be, but
I still think that I have very good intuition. That allows me
to say that I don’t agree with what some people are doing,
and that there are better approaches. I have my own ideas
which to my mind are superior. Whether this is actually true
remains to be seen. My intuition is that the way I approach
things eventually will bear fruit. I plan to continue with
that as long as I can. I don’t know how long I can continue
doing my own research, but as long as I have the ability to
do something, I’ll continue.
Is it fair to say that the theory of general relativity or
the black hole doesn’t have much direct applications in
our daily life?
No, I wouldn’t say that. Maybe in three ways these theories
do affect people. One is that general relativity has direct
influence on machines such as GPS that need corrections
from general relativity, but that’s not the main thing. General
relativity also becomes important if you realize that things
in the universe, like heavy stars and black holes, show
behavior that you can only understand with general relativity.
Furthermore, you can use gravitational waves, not yet now
but in the near future to find new information about heavy
objects in the universe, for instance black holes, which we
only understand properly if we understand how general
relativity works.
Now there are two other things, one is the applications
in neighboring fields. Perhaps direct applications of GR are
not tremendously big in science. Most topics in science do
not really need general relativity to understand them. You
don’t really have to know all the details of general relativity
to understand how a star works. However, general relativity
has shown the generic structure of how a force can arise.
We notice that the basic feature that makes a force work is
curvature of space and time. Now the concept that forces
can arise by having some sort of intrinsic curvature, has
been used by Yang and Mills, who realized that we can use
principles very similar to general relativity more generally in
particle physics, which led to their theory. They noticed that
there was a basic similarity between electromagnetism and
general relativity in that these both need some local gauge
fixing. In the case of general relativity it is the coordinate
transformation while in the case of electromagnetism that
is the gauge transformation. There are many similarities
in these two theories and so they realized that if that’s the
situation, maybe other forces exist that are based on the
same principles, and that could also act as forces between
particles. Thus they discovered the Yang-Mills theory,
today a very important, essential ingredient in all of particle
physics. Today we cannot understand particles without these
Yang-Mills forces. It was fairly directly derived from general
relativity, or at least general relativity was the big prototype
of a force based on geometric structures; and Yang-Mills
theory is based on the same idea. Yang-Mills theory is very
important in the subatomic world. Without it you wouldn’t
understand how a nucleus really works.
The third important thing is simply the fantastic way
nature challenges us, to figure out how things work;
general relativity is a marvelous mathematical structure. It
forces us to think very precisely, how to solve complicated
mathematical equations using approximations. You can
find only a handful of exact solutions whereas everything
else can be solved approximately. We have to understand
what it means to make an approximate solution in general
relativity and this is a big intellectual challenge for mankind.
An even greater intellectual challenge comes when one tries
to combine particle physics with general relativity. The very
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tiniest structures in nature that can exist are not properly
understood, and properly understanding them would require
general relativity, particle physics and quantum mechanics
all combined. This forces us to consider everything that
exists in the universe, put it all together and turn it into
the grand synthesis called Grand Unified Theory. This has
not yet been achieved and I think that the reason for this is
that humanity hasn’t been able yet to grasp this enormous
challenge. Thousands of people are tied to it but they all have
their intellectual limitations. They’re only humans and you
have to be superhuman to understand the whole problem
as one unity. This is such a marvelous challenge lying in
front of us, that many of my colleagues cannot leave it there.
They see the problem, they see quantum mechanics, general
relativity, the universe and cosmology, and, like I do myself,
they realize that we must be dealing with one grand structure
of something. How to formulate such a grand structure? A
mathematician only needs equations and then expects to be
asked how to solve the equations. But in physics, you don’t
understand the solutions, because you don’t understand
the equations. Find the equations, find why the solutions
are relevant and try to understand the world we live in this
way. This is an enormous challenge and I suspect that you
need some, say, computer intelligence to solve the problem
because humans are too restricted.
If we want to promote the physics research in Singapore,
how would you convince the people from the National
Research Foundation to do research in physical science?
I think you should capture people’s imagination and show
how physics, or science in general, has transformed the whole
world society into what it is now. We have airplanes, automobiles, phones, GPS, television and all such. The information
technology has modified the world. When I grew up there
was no internet, there were no mobile phones, and these
have completely changed our world. The whole world has
become a village, we can all contact each other no matter
how far away we are from each other. That’s an enormous
change. What about science? I think our message should be
clear, I see a lot of science in our future that will continue to
change this world. I think we are just at the very beginning
of the information revolution; it will go a lot beyond what we
see now. We’ll have intelligent computers and they’ll look at
us and say “A person. I think I know what your problem is
and I’ll solve it for you.” That kind of developments, although
still in the distant future, will change our society even more
completely than what has happened in the past.
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We see that science is progressing forward at a speed
faster than ever before. New observations and discoveries
are brought to surface every day. What is your prediction
on physics in 50 years?
That’s hard to say. The problem of quantizing gravity is bound
to be solved, and I think it will be solved. We will understand
how to do gravity correctly, I don’t see why not. This is a
theoretical problem. We are getting there and I think we
know much more than 30 or 40 years ago about this topic.
I cannot see why there should be any fundamental barrier.
This is only one of many theoretical questions. As for experiments, we see nearly every day that people do, or suggest to
do things that have never been done before. Thinking of the
large astronomical telescopes in high mountains and outer
space, you will see telescopes of kilometers in size, creating
images much sharper than anything in existence today. We
will know other planets in our neighborhood, and around
other stars, and we will learn how the universe works, how
galaxies cluster and shape. We will understand the universe
much more precisely than today. I think these things will
happen, not always as quickly as planned, but we will eventually succeed and get humans to populate the solar system.
Science will continue to transform our society.
It took almost 50 years from the establishment of the
Standard Model to the discovery of the Higgs particle. Is
the pace of physics development slowing down compared
with what it was 50 years before?
I hope you are wrong. I still believe that the twentieth century
was the golden age of science. Imagine the beginning of the
twentieth century, what changes have taken place since.
Before the twentieth century there were a lot of sciences
developing, and there will be sciences after the twentieth
century. But the twentieth century is the golden age, where
we saw an exponential growth in scientific activities. I hope
it is not the end yet. I hope the twenty-first century will be
comparable to the twentieth, but I have fears that it will not
be going as fast as one might want. Some people say that once
the computers become smarter than humans, there will be
great accelerations. Will this happen or not? Some people
say it will. Science will be done exclusively by computers. I
have no way to foresee what that will bring us.
I read that you are an ambassador for the 'Mars One'
project which is planning manned trips to the surface of
Mars. What’s your vision for the project and what could
be the implication for the future of human beings?
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My first reaction, probably like everybody else’s, was that I
told these guys: ‘you are simplifying things far too much.
This is much more difficult than you think it is’. I still believe
that is true, but what I did appreciate is that they investigated
every aspect, not only how to make a space ship, and how to
make air and water from what you have on Mars, but they
also thought about how to earn the money to make such a
trip, how many people you can send, how they are going
to feed themselves, how they can live together for so long.
One of the conclusions they drew is that the return trip will
be much harder, much more expensive, and much more
dangerous than the trip towards Mars. “So”, they decided,
“we can offer a one-way trip, but not a return”. Therefore the
sensible idea was that people who go must be completely
aware that they will not be coming back. They will need
to make life reasonably comfortable for these people and
reasonably diverse. My problem with this project is that it’s
still presented as being simple. The dangers are much bigger
than they seem to realize. I see some fundamental hurdles
and obstacles that I think will hold them back much more
than they realize now. Yet the idea of having made such
extensive considerations – I like it very much. I think in the
distant future, there will be people on Mars living in colonies.
This will only be possible with further advances in science,
whereas my friends here think they don’t need to invest in
science – they want to use what’s known today. What’s known
today should be sufficient to get to Mars. This may be true
on paper, but life will then be very harsh – I think it will be
too difficult for me to stay alive out there. Today, although
it is in principle possible to go to Mars, I think it is still too
dangerous; there are too many unsecure factors.
I know that a lot of other hurdles and obstacles will be
encountered, that will make the trip much more expensive,
and the project will keep being postponed for many more
years. But as I said, I don’t care about that so much. I like the
whole idea of making explorations – go on with it, and see
how far you get. Maybe you don’t actually make it to Mars,
but you’ve made the best attempt by far. You’ve made out a
plan. Maybe the plan doesn’t succeed, but there will be new
generations who understand what you’ve missed, and they
will start from there.
For instance, the idea that was suggested, is to build some
simple pre-fabricated houses, like balloons and domes, in
which you live. But other investigators think it’s better to
look for natural caves on Mars. Living underground provides
much better protection against radiation, leaks and meteoroids. If you can live inside a cave, that may actually be more
interesting also. Anyway this requires more science and more
time. So that may be a next generation of plans. Now just let
this continue and see how far it gets. This whole project to
me is an interesting scientific experiment all by itself. Can
one build, and maintain, an artificial ecosystem on a place
like Mars? It will be very difficult. But it should be possible.
I came across your website on ‘how to become a good
theoretical physicist’ and it is a really comprehensive site.
How much work did it take to put together such a wealth
of information and what’s your vision for it?
Oh that wasn’t too much work because I’ve been teaching
theoretical physics for a long time, so I know which subjects
you need to know to become a theoretical physicist. If you
have studied them all and understood what they are all about,
you can become a theoretical physicist. I get many questions
from outsiders saying: “I know nothing about mathematics,
but I want to read theoretical physics”. If you don’t know
mathematics, first step is to study that because you do need
it. People ask such questions all the time. Now I have this
webpage, so that I can say, go to this page and see what you
need. People also ask, I’m from a developing country. I don’t
have access to university, or, I’m old. What should I do? My
first response is, try very hard to get to a university because
it forces you to learn things that you don’t want. You think
they are unnecessary, but that is often not true. The things
you think are unnecessary are actually part of the education
you need to understand. If you go by yourself, you will be
tempted to skip the things you don’t want and that is probably
not a good idea.
Do you believe someone will be so serious as to finish
them all?
I get very positive feedback for the website. People say, “It’s
changing my life, because now I know what I need to do.” Of
course, the site reflects my own opinion. You don’t have to
follow my opinion. Some people say that’s a lot of work. Yes
it is a lot of work. If you want to be a good football player, a
pianist, or an artist, you also have to invest in yourself. This
is a kind of investment.
Can someone really become a theoretical physicist even
after studying all the notes?
I think only super humans can do that. Normal people will
encounter problems, of all sorts. They may not have enough
money to sustain themselves while doing the study. They
may also hit on problems of understanding. If they don’t
understand exactly what is being said in the lecture notes,
then they could go off in the wrong direction. We’ve seen
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quite a few very intelligent people nevertheless at some
point go off in the wrong direction, and they are no longer
promising scientists. So university is very important. The first
thing I try to persuade people to do is to enter somehow into a
university. If you really can’t, the website will roughly tell you
what theoretical physics is all about. But start with using only
these pages and nothing else. Of course you have the whole
internet, but you don’t see very often that people can do very
hard things by just surfing the internet – there are too many
distractions on the internet. If you know where to look, you
will find very good sites and you can learn a lot, but you will
also find sites where people got it totally wrong – these are
usually the shouting people. If you are not sufficiently well
prepared, you might fall in any of these traps.
David Gross and Edward Witten just wrote an essay on
WSJ about China’s plan of building the “Great Collider”.
If the project evaluation committee asks for your opinion,
what do you want to say to them?
I am very much in favor of this project in China, if for
nothing else then for the new competition they will provide.
At CERN, physicists are also dreaming of making an 80
kilometer circle, so they can quadruple the energy at LHC
today. They will then have a new accelerator. But if the new
accelerator has no competition, it will take ages to complete.
For instance, in the last couple of years Fermilab gave a strong
drive for LHC not to slow down because LHC was hitting its
own problems, postponed by a year and then another year so
it became operational much later than planned. People were
concerned that Fermilab may discover the Higgs particle
first. One major concern for CERN was that they might be
too late, so they should better hurry up. And so, they worked
very hard to get LHC ready in time and they did find the
Higgs particle. So this is kind of a race. Science flourishes
when there is competition, like the space competition in the
Cold War, about who will get to the moon first. Without the
Cold War, this would not have happened, and there would
still have been nobody on the moon today. So the whole idea
of China just mentioning that they might make an accelerator
already spins things up. Now at CERN, they are thinking
very hard about the next generation accelerator and how to
continue to keep science alive, because after 20 years LHC
will no longer produce anything new. It will have done its job.
CERN must do something else. If there is no competition, it
will take ages to build the new machine. Now the Chinese
may get what they need to make new discoveries at 40 TeV
or 100 TeV, a good motivation to CERN to push it. So I like
the idea of having more competition in this field.
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What do you expect to be discovered at such large
colliders?
Well that’s the whole point. If we knew what will be discovered we wouldn’t need to build such a machine. We need
it because we don’t know what to expect. For a long time
people were completely sure that the Standard Model will
break down. The questions are where and how it will break
down, what will be the new ingredients and fundamental
building blocks, like new kinds of quarks, new objects inside
the quarks and so on. The most popular way is to search for
supersymmetry and detect signs of superstring theory being
the way to look at things. There are some more novel kinds
of theories but one option that people usually don’t take into
consideration is that the Standard Model, for a very long
time, may continue to be basically the final word, and there
will be no extensions to the Standard Model for quite some
orders of magnitude of scales. It is conceivable, still not very
likely, but it is not impossible. If it is really discovered that
the Standard Model comes out without scratches, it will be
the problem of the Standard Model. The Standard Model
itself is not a perfect mathematical construction. There are
weaknesses in the whole concept. If we find out nothing
else, then nature itself will have different answers. It is a very
strong model, but this means that you have to work out the
Naturalness Problem. Very likely this has to do with the
gravitational force. Many of us do believe that if we attempt
to put gravity in, everything will change.
Is that true that you have actually found asymptotic
freedom or the scaling properties of the Yang-Mills
theories, e.g. QCD, but didn’t publish the result?
This history is very complicated. I was not the first, not the
last. There was a Russian physicist, (Iosif Khriplovich), who
made similar remarks but was ignored. With hindsight, we
can roughly reconstruct what has happened. People couldn’t
imagine that theories such as QCD would be asymptotically
free, because QCD is not more special than a scalar theory,
or theories with just fermions and scalars, or fermions and
abelian vectors. Why should non-abelian vector fields be so
special? If at all scales everything has the same sign, it indicates that the theory will destroy itself at short distances. To
such extent, that nothing works anymore at short distances.
This became the prevailing view: quantum field theory itself
is carrying its own seed of destruction.
It was rather mysterious as to why QCD is asymptotically
free. It has to do with strong magnetic forces and colour
magnetism being the dual opposite of colour electricity. The
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From left: Yuyang Cai, Prof ‘t Hooft and Dr Chi Xiong.
Yang-Mills gauge particles have large magnetic moments,
and these magnetic moments act in the other direction,
making the theory asymptotically free. This is highly nontrivial and was not expected. When Landau first asked the
question about the scaling of the theory of QED (I am not
sure if this story is confirmed, not in any books), his first
calculation had a sign error. So he thought QED is asymptotically free. Some student pointed out the sign error and
Landau was so furious that he thought that quantum field
theory is a mess. My advisor Veltman looked into the experimental data and found that the weak interaction behaves like
a Yang-Mills theory. He thought there must be something
good about Yang-Mills theory and asked the question about
its renormalizability. In the West, people like Murray GellMan had basically made the same observation as Landau
but didn’t make the mistake. He thought maybe there is a
limit to the definition of the strong coupling constant and
there is a fixed point. I never had much confidence in such
a theory because the fixed point is in the strong interaction
domain and the theory is difficult to handle, so you have a
theory based on very sloppy mathematics, and I don’t like
it. Symanzik thought those fermions and gauge fields only
make things more complicated, a scalar theory should show
it all. But scalar theories are not asymptotically free, so I
suggested that he should look into the Yang-Mills theory,
but Symanzik didn’t believe that. Thus, both the East and
the West, although they do physics in different ways, were
convinced that no theories are asymptotically free. Some
people concluded that a theory should not be based on
perturbative expansions at all. If that is the way nature works,
then I don’t want to be a physicist anymore because I do want
to do perturbation expansions.
When I was a young student I didn’t know all these papers
and didn’t quite understand why people were so hostile
towards quantum field theory. The Yang-Mills theory was in
the beginning of its formulation and I studied the Yang-Mills
theory and asked the question how does it scale. The scaling
was fine and asymptotically free (I didn’t use the word), but
I didn’t realize that I was the only one who had done the
calculation at that time (1971). People like Symanzik didn’t
believe it, and he told me that if what I said is true, I should
publish it immediately. But I got hooked to do something
else and postponed my publication. Veltman told me that
if I have a theory for strong interactions I should explain
why quarks don’t come out. Then the large-N expansion
came along, which showed that planar diagrams dominate
at large N. Gross, Wilczek and Politzer did the calculation
and had the right idea of publishing it, and to formulate the
conclusion that this must be related to understanding why
quarks do not come out.
Do you think the new generation of university students
today is any different from when you were in university?
I think science has grown enormously. When I was a
graduate, there were many undergraduate students at our
institute, but only a handful of graduate students, just only
5 or so in my field. We all knew each other. There was no
divide yet in particle physics and statistical physics – it was all
called theoretical physics. Now the department has become
so big that you don’t know all the other students any more, let
alone the undergraduates. Also another big difference is the
urge to get your thesis ready within 4 years. In the old days,
many of my friends took much more than that to produce
their thesis. The whole point is that the thesis has to be a good
thesis. If you need to take more than 4 years, so be it. Now
it’s an institutionalized problem. There are rules that don’t
allow you to take more than 4 years. That’s a short amount of
time considering the level you had to start off from. First you
have to learn the subject, learn the problems and come up
with solutions. That is very a tough assignment, and today it’s
even harder than the old days because our field of science has
grown enormously. You have to specialize much earlier and
in a much narrower domain of science in order to produce
a thesis. I think these are important changes.
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Prof David Gross's 75th
Birthday Conference in
Jerusalem
Lars Brink
Chalmers Institute of Technology
A
conference "Quantum Field Theory, String Theory
and Beyond" was held at the Israeli Institute for
Advanced Studies, Hebrew University in Jerusalem,
Feb 28 - March 3. The first two days of the conference was
devoted to a celebration of David Gross' 75th birthday. David
Gross was awarded the Nobel Prize for Physics in 2004
together with David Politzer and Frank Wilczek for their
discovery of asymptotic freedom in the theory of the strong
interactions, Quantum ChromoDynamics. David Gross is
a frequent visitor to Singapore and a strong promotor of
fundamental physics in Asia. He last visited Singapore and
IAS in January to take part in The Global Young Scientists
Summit (GYSS) 2016 and in the memorial conference for
Prof Abdus Salam.
The conference had gathered a large number of friends,
collaborators and students of David Gross as well as many of
the leading quantum field and string theorists from around
the world. The list of speakers for the first two days was Curtis
Callan, Andy Strominger, Lars Brink, Sasha Polyakov, Lars
Bildsten, Hirosi Ooguri, John Iliopoulos, Gary Horowitz,
Spenta Wadia, Eric Verlinde, Edouard Brezin, Igor Klebanov,
Marc Henneaux, Nati Seiberg, Tom Banks, François Englert
and Eliezer Rabinovici. They covered a vast area of modern
physics and Callan even talked about microbiology. Even so
these were subjects that David Gross had influenced one way
or another during his long and remarkable career. In addition
to the physics talks, there was a banquet at the restaurant of
the Israel Museum, attended by all conference participants
and by David Gross's family.
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Prof David Gross chatting with speakers and participants of the conference.
From left: David Gross, Jackie Savani (Mrs Gross), Eliezer Rabinovici, John
Iliopouolos, Dieter Luest, Lars Brink and Hirosi Ooguri.
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Unpublished C. N. Yang
Interview on Teaching
and Research in Physics
Yu Shi
Department of Physics,
Fudan University, China
David Waxman
Center for Computational Systems Biology,
Fudan University, China
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Abstract:
This is translation of a Chinese transcript of five conversations between Prof. C. N. Yang and others in Beijing
in 1986. In the conversations, Yang gave his views on the state and development of physics at that time, and
the relationship between physics and philosophy. The conversations also contain Yang’s reminiscences on the
creation of Yang-Mills theory and his advice to young people, especially those in China.
photo courtesy of University of Science and Technology of China
In the early summer of 1986, Professor Chen Ning Yang was
invited by the Graduate School (Beijing) of the University
of Science and Technology of China to give a series of five
lectures. China was just beginning to open up, and universities did not have adequate halls for this purpose. As a
consequence, the lectures were given in the Friendship Hotel.
The audience consisted of faculty and graduate students
from universities all over China. At the end of each lecture
there were informal question (Q) and answer sessions, for
which proceedings were later published in Chinese1.
Thirty years later, these question and answer sessions
make for very interesting reading, from a historical perspective, and also from the perspective of the present. The
following is our translation.
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Q: Please tell us about the goal of your lectures.
Yang: The subjects of the lectures were quite different, I
think, from what was expected. It may have been thought
that I would teach a lot about gauge field and high energy
physics. If so, the audience was surprised. The contents of
the lectures included neutron interference, the AharonovBohm effect, flux quantization, holography, free electron
lasers, quasi-crystals, high-energy elastic scattering, Dirac
monopoles, fiber bundles, and Non-Abelian gauge fields.
I intentionally did the lectures this way because of two
goals I had for these lectures.
Firstly, I am interested in these subjects, many of which
reflect the genuine spirit of 20th century physics. Some of
these subjects are still under development, such as quasicrystals and free electron lasers, and there will be great
advances in the next twenty or so years and I thought that it
would be worthwhile to introduce them to you.
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Secondly and more importantly, through the selection
of the topics, I hoped to inform the audience that they
had better pursue new subjects in physics. What I wished
to emphasize is distinct from the spirit of the teaching of
physics that has taken place in China in the last few decades.
Frankly speaking, physics students in China have been
largely accustomed to sterile reading. I think the situation
should be urgently changed. The whole social environment,
arising from the attitudes of their parents and the media,
has misled students, so that they have followed the wrong
direction. Consequently, there are many students who are
hard-working, well trained and very knowledgeable about a
specific part of the subject, but their breadth of knowledge
is narrow, and they have tended to develop expertise in
highly mature aspects of the subject. This is very harmful.
One of my goals, in the choice of the subjects I discuss here,
is to introduce my viewpoint about physics to you. It is not
necessary that everyone will be interested in all of the topics,
however, if you think about what kind of topics these are,
then hopefully you will begin to appreciate which physical
problems are worth attention and further investigation.
In their studies, many students form an impression
that physics is just calculation. Calculation is, of course, a
part of physics, but not the most important part. The most
important part is related to physical phenomena. Most of
physics follows from observation of phenomena. Physical
phenomena are the ultimate origin of physics. Without
contact with phenomena, it is not impossible for a student
or researcher to produce important work, but it is very
probable that what they do is in the wrong direction and
purely formal; they will miss the key point of physics. All the
important physicists I know attach great importance to real
physical phenomena. This is the strong impression I formed
after I went to the USA to study. When I was a graduate
student at the University of Chicago, I watched Fermi and
Teller pay great attention to physical phenomena. Sometimes
they performed a complicated calculation, but they were
strongly focused on physical reality. During the period of
1948 to 1949, Fermi investigated renormalization, but he did
not pay more attention to this than to physical phenomena.
Renormalization was only one of many physical problems
he considered. There is now a common situation that many
people play games with the mathematical structures of
physics, at the expense of studying real phenomena.
I have spoken about the teaching of physics in China
many times in the last few years. I have given a speech “40
years of learning and teaching”, which has been collected into
a volume with the same title. I talked about it in Hong Kong
in 1983, and later in Beijing and also Shanghai. It includes
the following comments: “I have visited China many times
since 1971, and discovered that there are the so-called ‘Four
Courses of Mechanics’ (classical mechanics, electrodynamics, statistical mechanics and quantum mechanics) in
physics departments in the universities, which depress the
students. No one denies the importance of the ‘Four Courses
of Mechanics’, which form the backbone of physics, but
physics with only a backbone is a skeleton. Physics needs a
backbone, but it also needs flesh and blood. Only with flesh
and blood can physics come alive.
I think this topic touches on a very important problem.
In the West, especially the USA, young people often lack
training, but they have a spirit of fearing nothing, and are
fond of thinking about new things, which are often close to
experiments and real phenomena. I hope all of you pay more
attention to new things, to living things and to things closely
related to phenomena.
How could you actually achieve this? I have a concrete
suggestion. There is a magazine entitled Physics Today in
America, which is very good. On the first few pages of each
issue, recent progress in physics is often introduced. These
articles are well written and demonstrate deep thinking. The
topics of recent progress that are introduced are, mostly,
closely related to experiments, though some are purely
theoretical. These articles are very readable and are only
introductions, without going into details. For myself, I often
read these articles to get to know about new progress of
subjects I have heard of, or to get to know from which papers
I can read about the new developments. There are many such
articles with wonderful things mentioned. I suggest that
graduate students and faculty members jointly look at new
topics in each issue. In the beginning the study may not be
very deep, only gaining knowledge about what is written. If,
however, someone is interested in a particular topic, and is
willing to read more of the literature on this, and present on
this, then the whole group can go deeper. Many of the topics
I have lectured on have been covered by Physics Today in
the last 5 to 10 years. If, in a department of physics, there is
a seminar series on the reports in the introduction of each
issue of Physics Today, then this department will be doing
a very good job at keeping up with recent developments.
Q: Please tell us about your expectation regarding the
development of physics.
Yang: Different physicists have different viewpoints on this
question. Let me tell you my personal ideas.
There has been great progress in physics in the 20th
century. This was because of developments in experimental
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techniques. At the end of the last century, experimental
techniques reached such a level that people were able to
perform detailed spectroscopic investigations on molecules,
atoms and nuclei. Spectroscopy has provided a large amount
of data on atoms and molecules, and many problems that
attracted attention in the first quarter of the 20th century
came from spectroscopy. Indeed, this led to the formulation of quantum mechanics. In the 1930s, accelerators
promoted the development of a new field, namely nuclear
physics. Following the dropping of the atom bomb, governments of many countries linked progress of physics to the
future of their countries after the Second World War. As a
consequence, a large amount of money was put into physics
research. Together with industry, this created conditions
for great progress in various aspects of physics. There have
been astonishing developments in two important fields,
namely high energy physics and condensed matter physics.
However, further development of high energy physics is
facing difficulty. It is difficult to do high energy experiments,
as too much money is needed. This does not mean there will
not be important achievements in high energy physics. For
example, I have no doubt that if found, the discoveries of W
and Z particles will become cornerstones of the subject. But
the number of people working on high energy physics will
decrease over time, and the achievements of each person in
this field will also decrease. Nowadays, in conferences on
high energy physics, it is common that not many important
new results are reported. I suppose high energy physics,
in the next 30 years, will be in a difficult period. This does
not mean there will not be important work. Neither does it
mean there will not be people working on it. Nevertheless
the situation will not be a prosperous one. Although there
are many smart people working on theoretical high energy
physics, the theories will not be verifiable in experiments in
the near future. Indeed the modern theoretical working style
is very different from the past, and working with the door
closed (on phenomena) has become inevitable.
On the other hand, condensed matter physics and areas
related to technology will make great progress. It is relatively
easy to have achievements in these areas.
Q: What is the current situation in theoretical physics?
What period in the past is it comparable with?
Yang: Physics is very broad, and differences with the past
lie in every direction. However, in most areas, the spirit is
the same as in the past. For instance, in solid state physics,
there have been great advances in experimental techniques,
and there have been qualitative changes in methods of
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Asia Pacific Physics Newsletter
investigation. You cannot work on it at home, as was the case
one hundred years ago, but its spirit is still very close to that
of the subject 50 years ago.
Fundamental theoretical physics is based on particle
physics. As I said above, particle physics experiments are
increasingly expensive, and will inevitably decline in the
next 30 years. With fewer and fewer experiments, the people
remaining will be mostly theoretical. Some of them are very
smart and it is inevitable that the field will become more
and more mathematical. Already, fundamental theoretical
physics is very mathematical. On the other hand, field theory
and statistical mechanics are gradually being connected
together. Statistical mechanics is closely related to condensed
matter physics. Therefore, field theory is now increasingly
connected with statistical mechanics and condensed matter
physics. People at the starting stage of their career should pay
attention to these points. As to the conclusion, it depends on
what you like, what you have learned, and what opportunities
you have.
Q: What problems do you think there are in scientific
research in China? How can young people join research?
Yang: Let me focus on some general viewpoints that do not
necessarily apply to everyone. In China, there are many able,
creative and persistent people. No one doubts that China
can be at the forefront of developments in physics. But
there are also many problems in China. There are problems
in industry, in city construction, in education, in living, in
families, etc. There are many problems. Why, with so many
smart and talented people, are there still so many problems?
The answer is very simple and is unique. That is, China is
poor. So earning money is the number one thing, at the levels
of the individual and country. This does not mean everyone
should go on to earn a lot of money. Instead, it means that
the whole society should be economically successful. This
is an absolute necessity. For many years I have regarded this
as the most important thing for China. One should have it
in mind when making important decisions. Hence I agree
with a slogan in China: Twice double the total productivity
of industry and agriculture by the year 2000. This slogan is
rational, instead of irrationally making the goal too high.
It will be remarkable to realize this goal in the year 2000.
This will not only be important for China. It will also tell
developing countries that are similar to China, that to make
as great a development as China is possible if the goal is clear
and achievable. By 2000 everything will be different in China.
For the overall benefit of every individual, my understanding
is that everyone should try to cooperate to achieve this goal.
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If an individual has made a contribution to the process of
realizing this goal, they will recall it with pride in the future.
For many years, I have told people studying physics not to
enter high energy physics unless you feel you have to. High
energy physics has nothing to do with China’s twice doubling,
and even has a negative contribution, as high energy physics
is very costly. This does not mean high energy physics has
no importance. Certainly it has importance, but the problem
with China is that of “twice doubling” rather than that of
high energy physics.
I feel that too many Chinese students in primary schools,
middle schools, and universities, and even in graduate
schools, overvalue studying. Studying is a tradition of China,
and it has its advantages. But just because of this, it is not
so easy to judge on its true value. In the West, especially in
the USA, studying is not regarded to be as important as it
is in China. In China, especially in cities, parents wish their
children to enter good middle schools, good universities,
and obtain master degrees and doctoral degrees, and even
higher degrees if there were any. This is harmful to China’s
economy as well as to the children themselves, as this is not
achievable by every child. Here, you are all graduate students,
hence you are all good at studying. If you are very happy in
doing this then you may think about the problems I have
lectured on. I do not agree with the very hard studying that
occurred in the past in China. If you are very unhappy with
study, you may think about whether doing something else is
better for you and for society. For example, maybe you can
make a better contribution if you go to a small factory, as
you have some knowledge in physics, can speak a foreign
language, and know something about the world. With such
conditions, studying physics without joy may not be the best
way forward.
Q: In “40 years of learning and teaching”, you say the
probability of success is higher if a young person enters
a new field and grows together with it. What fields do
you think have good prospects?
Yang: Quasi-crystals is an example that I have already
mentioned. It is a new subject, and some of the basic concepts
have not been made clear. Any new direction, with broad
connections, has good prospects. If quasi-crystals could only
be produced under very special conditions, the prospect for
the field’s development and impact would not be very good.
But such is not the case of quasi-crystals, as we know.
Another example is if a new direction of experimentation
occurs, as when two fast moving giant nuclei hit each other.
This must lead to many new and interesting phenomena.
Such phenomena may not be the most fundamental, but are
still worth studying.
Yet another situation is the technology that is developed
in a new field, which enables people to study phenomena that
could not be previously studied. For example, now people
can produce high powered lasers, with pulsed electric fields
that are stronger than the electric fields inside atoms. Hitting
an atom with such lasers can strip a whole shell of electrons.
Such experiments are still very primitive. Entering such a
field can easily lead to success.
If you work on renormalization of quantum electrodynamics, it is not easy to succeed, as it has a history that spans
decades, and many very smart people have worked on it.
How can you guarantee that you can do better than these
people? This is not to say that working on such topics should
be stopped. I am answering a question about which field it is
easier to succeed in. To sum up, a field, new in either concepts
or technology, or a new experimental direction, has better
prospects than a well-trodden field.
Q: How should a physicist regard philosophy?
Yang: The word philosophy has many different meanings.
In articles by Western physicists, there are two different
meanings, one is the philosophy referred to by philosophers,
another is a kind of view on physical problems, at a long or
intermediate distance.
Q: Does the second philosophy refer to the epistemology?
Yang: No. Epistemology, as defined by Shoishi Sakata, is
a true philosophy, of the first kind. To give an example of
the second kind, someone says: “Grand unified theories
cannot possibly succeed.” You say: “I agree.” Then the first
person says: “We have the same philosophy.” No matter what
words are used, the second kind of philosophy represents a
viewpoint, namely, what kinds of problems receive attention.
This has an important long-term influence. It decides what
questions people like to raise, what questions they do not
like to raise, what questions they would like answered, and
what questions they do not care about. Also, the second
kind of philosophy influences what methods people like to
use, to solve a problem once the question arises. This sort of
philosophy has much to do with one’s style and preferences,
and has a decisive impact on one’s long term achievements in
research. Everyone develops a philosophy of the second kind,
out of their experience. Everyone should be reminded that
it has important effects on their research, and they should
be aware of it, to some extent.
As to the first kind of philosophy, I think it has a one-way
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relationship with physics. Physics influences philosophy, but
philosophy never influences physics.
Q: Einstein thought he had been strongly influenced by
Hume’s and Mach’s philosophy.
Yang: I do not agree with this saying. I think his success
was because of the second kind of philosophy rather than
this reason.
Studying physics is like looking at a large painting. The
structure of the whole of nature is like this painting. There are
several ways of looking at a painting. Sometimes one should
combine different ways of looking. One way is to study it in
detail, at a close distance. Since the painting has been made
very carefully, different parts are different from each other,
and you have to carefully study their details. Another way
is to look at it from a great distance, where you may notice
some patterns you cannot see at shorter distances. This is
what is present at large scales. Certainly there are also views
at intermediate distance. Physics needs views captured at far,
intermediate and short distances. Certainly, if you can see a
pattern that can be seen from a great distance, you make a big
contribution. But this possibility is very small, almost impossibly so. You thus have to start at a short distance. Generally,
the direction of knowledge is from near to intermediate to
great distances, rather than the other way around.
An example of the above is that after its foundation,
quantum mechanics strongly influenced philosophy, but
neither Heisenberg nor Schrödinger started from philosophy.
Instead, they started with atomic spectroscopy when they
formulated quantum mechanics.
I entirely disagree with the idea of Sakata. I think Sakata
has made some contributions to physics, but not out of his
philosophy, instead, they originated in his understanding
of physical reality. I disagree with his self-said origin in
philosophy. His way of starting with philosophy went
nowhere. I think he would have achieved more had he used
less philosophy.
Q: What do you think of superstring theory?
Yang: Superstring is a topic of great current interest in theoretical high energy physics. I estimate that there are about
100 people with PhDs working on it. I hardly believe this
theory will turn out to be right in the end. The basic concept
in high energy theory is the field. This was started by Michael
Faraday and through James Maxwell, and to the present,
the idea of field was developed with many ups and downs,
with countless experimental tests. The superstring started
by generalizing the notion of field, without comparison with
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Asia Pacific Physics Newsletter
experiments. Now there are many papers on superstrings,
but none of them has anything to do with experiments.
Very likely it is a castle in the air, a dream. In Stony Brook,
a graduate student asked me whether he should work on
superstrings. My answer was the following. There are many
important unsolved problems in high energy physics. There
are many beautiful mathematical structures in superstring
theory. If you are very interested in this subject and are very
good at doing it, with excellent intuitive understanding of
differential geometry and topology, you could work on it.
But if you regard this direction to be certainly right, then
you will be disappointed in the future, because the idea of
superstrings has too little contact with real physics. Having
little contact with real physics will not necessarily make the
subject unsuccessful, but the chance of success is quite small.
The mathematical structure of superstrings is very beautiful,
and if you work on it, you will absorb these beautiful aspects.
These may be helpful to your developing some methods
to resolve some real questions. From this standpoint, you
could go to do some work on superstrings. My words to the
graduate student include my attitude to all of this class of
questions concerning pure structures. It is very rare for an
idea from abstract mathematics to become very successful
in physics. You must be aware of this. Otherwise you could
be very disappointed later on.
One can look at the connections of mathematics, theoretical physics and experiments in the following way:
4. Mathematics
3. Theoretical structures of physics.
2. Combining theories and experiments.
1. Experiments
Parts 2 and 3 together constitute theoretical physics.
A pure theoretical structure is connected to experiments
through the second part. A pure structure will lose its
position in physics and disappear if it cannot be related to
experiments. The value in physics ultimately relates to experiments. Superstrings have not yet been related to experiments,
as in the second part.
If you ask me whether I, myself, will work on superstrings,
my answer is that I would never work on such a subject. If
I can make myself understand it in two weeks, I will spend
two weeks. But now it has become so complicated that I do
not believe that I can work out results known to others in
less than half a year. Because there are many smart people in
this field, half a year is a very large investment, And it is not
close to the physics I like. So I will not work on it. I know
that I can do the kind of mathematical calculations required
for superstrings. But if I were a graduate student, and my
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knowledge of physics had reached my current level, I would
certainly go to pure mathematics. There are many beautiful
things in pure mathematics. I should use my time and ability
to work on the things that really advance mathematics, rather
than go to work on things that neither advance physics nor
have long-term value for mathematics.
Q: Now there are also people doing phenomenological
work.
Yang: Those are far-fetched, far-fetched and far-fetched. Now
that there is a pure structure, some people want to connect it
to experiments in an ad-hoc way. As with superstrings, supersymmetry has not yet been connected with experiments.
Q: Please elaborate your attitude to supersymmetry.
Yang: Supersymmetry is very beautiful. Theories such
as supersymmetry will continue to develop in the future,
since the notion of symmetry is more and more important
in physics. Since fermions and bosons are not yet treated
symmetrically, contemporary theories are obviously
imperfect.
The left hand side of Einstein’s gravity equation includes
Rμν, while the right hand side includes Tμν. Einstein thought
the left hand side is very beautiful, but the right hand side
is not good. He said that the left hand side is made of gold,
while the right hand side is made of mud. He wanted to turn
the matter contribution, on the right hand side, also into
something geometric, and move it to the left hand side. To
geometrize the matter contribution needs a unification of
fermions and bosons.
The basic spirit of supersymmetry is very good, and has
something very beautiful. The first time when I saw papers
on supersymmetry, I did not believe it, as I thought the
Feynman diagrams of fermions and bosons are different. In
a certain theory, if the masses of fermions and bosons are
equal in the lowest order approximation, then the masses
will become unequal in higher orders. But my thinking was
incorrect: there are some field theory models where the
masses of fermions and bosons are equal in every order of
perturbation. Hence it does have some beautiful aspects in
some key points, but it still does not have anything to do
with experiments, after more than 10 years.
If you ask another question, whether you should enter
this field, I think you should be cautious. If you enter another
newer field rather than this one, and if you are both interested
and good at the subject, then it is easier for you to have good
achievements. In a mature field, where many smart people
have done a lot of work, what reason do you have for thinking
that you will do better than them? This is like panning for
gold, which is certainly better done in a new gold mine. This
does not mean that nothing can be panned out of an old gold
mine. But the possibility is lower. So I recommend panning
in a new gold mine rather than an old one.
Q: What do you think of supergravity theory?
Yang: Einstein’s gravity theory has a close relationship
with experiment. Nevertheless he was not entirely satisfied
with it. I have said that he wished to geometrize the matter
contribution on the right hand side, and move it to the left
hand side. It can be thought that supergravity is a beautiful
proposal to resolve this problem. But it still has not been
connected with experiments.
In Stony Brook, a graduate student from China wished to
work on supergravity. I asked him: “are you very interested
in supergravity?” He said: “yes.” He learned geometry well. I
said: “then you could work on it. You should obtain PhD in a
shortest period of time, and pay attention to other subjects,
such as solid state physics.” He is now the best student of van
Nieuwenhuizen. I believe he will excel in this field. I give
this example to illustrate that if some people genuinely like
to work on pure structures, and can do well, then let them
to do it. But if you have not yet decided what to do, and are
not as good as others at things like differential geometry,
then I think you had better work on physics closely related to
experimental phenomena, which is a safe way of training in
theoretical physics. Supergravity is a pure structure, and will
fade away if it cannot be related to experiments in 30 years.
Q: Where, in the four parts that you just talked about,
does Yang-Mills theory belong?
Yang: There were students asking me about this in America.
They said: “When you worked on gauge field in 1954,
wasn’t it also a pure structure having nothing to do with
experiments?” Indeed it did not have much to do with
experiments at that time, nevertheless, if you read our paper,
you will find that it has close relations with two theoretical
structures that have solid experimental foundations. These
are conservation of isospin and the Maxwell equations. Now
there is much work of adding flowers to silk, and for pure
structures without experimental foundations, which become
increasingly distant from experiments, it is very dangerous.
Ever since gauge field theory was put forward, I always
paid attention to it, but did not write many papers. I always
think it should not be carelessly changed to phenomenology.
In the 1960s, there are people who thought it wonderful from
the standpoint of pure structure, and did phenomenological
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work on it, amongst whom Sakurai was most notable. He
thought that the ρ meson is a gauge particle. I did not agree.
His way of doing things was very far-fetched. He wrote to me
asking why I was not interested in his work, in a complaining
tone. Perhaps I did not reply to him. I was certainly interested in gauge fields, but thought his way of doing things
was not good, so I had no way to answer him. Later, people
introduced the idea of spontaneous symmetry breaking to
gauge theories, thereby solving the mass problem of gauge
particles without violating the spirit of symmetry. This is an
important contribution. This experience tells us that many
beautiful pure structures may be related to experiments,
perhaps by a subtle revision. This is also the hope of people
working on pure structures. However I warn you that the
hope of success is very small.
Q: Are you satisfied with Higgs mechanism?
Yang: No. Everyone thinks this. It has its beauty, and fits
current experiments. But nobody believes it is the final
theory. Its idea is too ad hoc, and is without deep reasons
of physics and mathematics, so it will be replaced by other
theories. But it is very useful, for now.
Q: What do you think of the unification of gravitational
fields and gauge fields?
Yang: Comparing their formulae, one can find that they are
very similar. It is no problem that they have close relationship.
But what kind of relationship is still a controversial question.
The Fμν of gauge fields and the Rμν of the gravitational
field are both curvatures in geometry. The quantity Rμν is the
second derivative of gμν, hence Einstein’s gravitational field
equation is a second order differential equation for the gμν.
Now that the equation of motion of a gauge field ∂ μFμν =…is
a first order differential equation, the gravitational equation
should be a third order differential equation of gμν. This is
also an indication that Einstein’s gravitational equation needs
revision. In 1974, after the geometric structure of gauge fields
was clear, I put forward a new equation for the gravitational
field. But while I was able to write down the left hand side
of the equation, I was not able to write down the right hand
side. This problem has not yet been solved up to now.
Q: Please comment on the grand unified theory and the
role of gauge fields in it.
Yang: Grand unified theory aims to extend the successful
electroweak unified theory to also include the strong interaction. However, grand unified theory does not fit experiments.
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Nature is mysterious. Grand unified theory only simply
extends a successful existing theory. Without a new idea, its
lack of success is not surprising.
I think the direction of unifying more objects is correct,
and I believe that most theoretical physicists agree to this.
How they are to be unified in the future I don’t know. No
doubt gauge fields will play an important role in the unification, but perhaps it is not enough to only have this, perhaps
there ought to be new ideas that have not been thought of.
Q: What comments would you like to make on sub-quark
unified theory?
Yang: These are very speculative subjects. There are many
papers, and they have been investigated for many years. It is
not appropriate for young people, at the beginning of their
graduate studies, to develop in such a direction. Rather, they
should work on problems relevant to physical phenomena.
Q: What do you think of the fifth interaction?
Yang: Early this year some journalist reported a paper
published in Physical Review Letters, hence the whole world
knows there is the so-called fifth interaction. I do not believe
such an interaction with the interacting range neither long
nor short. If I were the referee, I would agree to publish this
paper, but I don’t think it would merit additional publicity.
You do not receive much news in China, so it is easy to be
dominated by some fragments of the news. Physicists should
have their own attitudes. Some attitudes may be wrong, and
should be revised in time. But with their own attitudes, they
would not be like weak trees that easily shake with the wind.
Some people like to connect some strange structure with
some rare experiments. It often happens, but the probability
of success is very small.
Q: Please tell us what you think of the phenomenological
theories of associated production.
Yang: Frankly speaking, work on this direction, abroad, is
without any value, since the people working in this do not
know what physics is. In China, in seeing a paper in Physical
Review, one often immediately makes an effort to study it.
This is often a disadvantage. Papers often come out in the
following way. A writes a paper. Then B says it is wrong, and
makes a revision. Then C says that B’s paper is wrong, and
makes a revision. You read the paper of C, and are trapped in
others’ puzzles without foundation. Regarding such things,
you should study the original experiment. It is relatively
easy to study new things. As it is new, it has not been made
PEOPLE
confusing by many papers. If you enter the field at this
time, which is now close to experiments, then it is easy to
obtain new interesting results. I have two suggestions: pay
more attention to new subjects under development, and pay
more attention to original phenomenon. If these two points
are implemented, then it is easy to be connected with real
physics.
Q: Please tell us what you think of chaos theory.
Yang: This is a new and interesting field. A few years ago,
I suggested to some people in China that they work on it.
Now it has had a history of 7 to 8 years. But it is still worth
working on.
Q: Please comment on finite temperature field theory.
Yang: Finite temperature field theory is very interesting. This
is a topic with depth. There are many papers on it, but I did
not study them. For such a problem, my general attitude is
the following. If I decide to work on it, I will start from the
beginning, without reading others’ papers first. Only if there
are some difficulties, after working for some while, do I go
to read others’ papers. Only in such a way do I digest their
work well. Around 1959, T. D. Lee and I wanted to discuss
W intermediate bosons, and electromagnetic interactions
of vector mesons. We worked from the start. After some
time, we noted that many of the papers of others were
wrong, though there were many. After a year, we became the
top experts. Finite temperature field theory is a very good
direction. If someone goes to work on it, I suggest that they
work from the start, not necessarily reading others’ papers,
rather, reading them after working for some time. This is like
arriving in a city for the first time. If you follow others from
the start, you may still not know about the city after several
journeys. If you try going around by yourself, the situation
may be different.
Q: What do you think of the early Universe?
Yang: There have been many papers on it in the last 15 years,
among which I suppose there are many interesting papers.
However, I have not touched this field. Such questions are
very speculative, which is not what I like working on. Some
people like working on such a field, and are very successful.
If someone is very suitable for doing such work, I think it is
a good direction for them.
Q: My advisor asked me to work on superstrings, but
I do not have the knowledge on supersymmetry and
supergravity. It will need a long time to enter the field,
time would be wasted if later it is found that the whole
idea is problematic and I give up. On the other hand, I
think life is determined by a biological field, and would
like to research on it, but I fear that it could be castles
in the air.
Yang: I understand everything you said except the biological
field. If you have a very original idea, you may think about
it in depth, but do not stick to it without limit, you should
also pay attention to other things. Let me talk about my own
experiences on this aspect.
When I was a graduate student in the University of
Chicago, I thought about the following question. In relativity,
there is a question of measuring a rigid body by using rulers,
which was not yet clear after many years of debate. Now that
only the observable subject can be established in physics
(now I think this idea may not be always correct, and needs
not to be regarded as too sacred), there is no rulers on the
fundamental level, and there is no ordinary measurement,
physics should not start from ds2 = gμνdxμdxν, as it is not
fundamental. One should draw the worldline of every atom.
These worldlines form a net in the four dimensional spacetime. Physics is the pattern of this net. At that time, I thought
this idea is quite reasonable, and is very fundamental. And
I told Fermi about it. He said: “it is interesting, you go and
develop it.” I thought for a couple of days, and could not go
on. From this episode, I draw a lesson that everyone has his
or her own line of thinking. If you have an original idea, it is
worth thinking about, but do not be obsessed with it. If you
are unsuccessful after a couple of days, you should move on to
another problem. Always thinking about one thing can make
one crazy. Another story is as follows. I had an idea, when I
was a graduate student. Noting that the Maxwell equations
have a close relation with the conservation of electric charge,
and given that conservation of the isotopic spin had been
confirmed by experiment, couldn’t there be another kind of
gauge field? I developed this idea for a couple of days, and
could not go on. After half a year, one year, I felt this idea is
very good, so I went back to try. I tried for several times, until
1954. Then the importance of this problem became clearer. To
use gauge fields to write down the interaction is a principle,
at least for a class of interactions. So I again tried to develop
my idea. At that time I was sharing an office with Mills at the
Bookhaven Laboratory. We added an additional term [Aμ,
Aν] on the right hand side of Fμν = ∂μAν - ∂νAμ, where the Aμ
are 2×2 matrices, and the difficulty was finally overcome.
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Nonabelian gauge theory was thus born. The lesson from
this story is that, if you have an original idea, do not give it
up easily, but do not stick to it indefinitely; you should also
pay attention to other things, and broaden your perspective.
This is like playing go, if you have a disadvantage at some
area, do not stick to it indefinitely: change to another area to
develop a territory. Afterwards, circumstances change, and
perhaps the old area becomes alive. So there are two points,
not only do not give up your original idea, but also work on
other things for some time. As to your biological field, I do
not understand this; you may discuss it with others.
and I have two points. One, Fudan University is a first class
university, the undergraduate physics education you are
receiving in Fudan can only be better, not at all worse, than
the undergraduate education in any American university.
Second, after your graduation from Fudan, many American
universities will accept you for graduate study and provide a
teaching assistantship, no matter whether you are sent by the
government or go by yourself, since Fudan has a very good
reputation in America. I think this is the best way for you
to study physics. Finding an arbitrary university in a hurry
does nothing good for you.”.
Q: What do you think of going abroad for graduate study
with self-support?
Acknowledgment:
Yang: My thought is, there are many many people in China,
studying abroad with self-support is nothing bad. Now that
we are discussing this topic, let me elaborate more. I have
two comments. First, there are many people from Chinese
mainland going abroad for graduate study, and many of
them did not go back after receiving their doctoral degrees.
This was anticipated. Many years ago, I said it in China. Now
many people care about it, regarding it as a great loss, and
very bad. I do not agree to it. Many people remain abroad, but
there are more people who haven’t gone abroad. So it is not
a big problem. In 1950s to 1970s, among those from Taiwan
studying abroad, those going back comprise less than 1 to 2
percent. But this did not stop the economic development of
Taiwan. Taiwan’s economy has its shortcomings, but it has
developed a lot during that period. Second, let me illustrate
matters by using a story. Three weeks ago, I was taking a taxi
in Hong Kong. The driver was a woman. I said: “You speak
good Mandarin.” She said that she went to middle school in
Beijing in the 1950’s. She asked what I do. I told her that I am
a physics professor living in America. She said very good, but
she had a question to ask me. She has a son who graduated
from a middle school in Guangzhou and entered the Physics
Department of Fudan University. His classmates all wanted
to go abroad. So does he. But to go abroad through CUSPEA
(China-U.S. Physics Examination and Application), there are
only seven or eight successful students each year. He was a
top student when he was in middle school, but the competition is strong in Fudan, and he felt that it was not hopeful
for him to go abroad through CUSPEA. So he worried very
much. Through an American organization, he made contact
with a university (I have not heard of its name), but 70 to
80 thousand Hong Kong dollars are needed. She asked me
what she should do. After arriving at the destination, I wrote
a note to his son. I wrote: “My name is Chen Ning Yang,
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Asia Pacific Physics Newsletter
We thank Prof C. N. Yang for his advice.
References:
[1] C. N. Yang, Proceedings of the Graduate School of the
University of Science and Technology of China (in Chinese),
October issue (1986), reprinted in Collected Papers of C. N.
Yang (in Chinese) (East China Normal University Press,
Shanghai, 1988).
ARTICLES
Superconductivity in a Terrestrial
Liquid: What Would It Be Like?
Anthony Leggett
Nobel Laureate in Physics 2003
Department of Physics, University of Illinois at Urbana-Champaign
Although it seems rather unlikely that superconductivity could occur in the liquid state under ambient conditions,
there seems to be no rigorous principle which forbids it. I raise, and make a first pass at answering the question: What
would be the anomalous macroscopic properties of such an “ambient-conditions liquid superconductor”?
I
t is a pleasure to have been invited to contribute to this
volume which celebrates the 90th birthday of the doyen of
contemporary condensed matter theory, Phil Anderson.
I thought I would take the opportunity to indulge in a little
piece of science-fiction fantasy, analogous to what was done
by the late novelist Kurt Vonnegut in his invention of ice-IX.1
Readers may recall that at the time that his novel Cat’s Cradle
was written, there were eight different known solid phases of
water, none of them stable above zero temperature Celsius.
Vonnegut (whose brother was a physical chemist) postulated
a ninth form, which would be stable at and above room
temperature, but which was separated from both liquid water
and the known phases of ice by a free energy barrier so high
that it had never been realized in the history of the earth.
One day a scientist synthesizes it in his laboratory, and it is
eventually released into the environment. What Vonnegut
implicitly assumes, but does not tell the reader (he is writing
a novel, not a physics textbook!) is that the transition between
water and ice-IX belongs to the small sub-class of first-order
transitions (which includes the A-B transition in superfluid
liquid helium-3)2 which are “hypercooled,” that is, which
have the property that the latent heat released is insufficient
to warm the system back above the equilibrium transition
temperature, so that the velocity of propagation is not, as
in the usual case, limited by the need to get rid of this heat
but only by the speed of sound. As a result, when the ice-IX
sample is released, the oceans freeze near-instantaneously,
with predictably gloomy consequences for mankind. Of
course, as far as we know, ice-IX is (thankfully!) a fiction,
but by thinking about it one learns quite a bit more generally
about the properties of first-order phase transitions.
The fantasy I am going to explore is equally improbable
but also perhaps equally fertile in its implications: a liquid
which is superconducting under conditions which are not
too remote from the ambient terrestrial ones (e.g., similar to
those under which existing high-temperature superconductivity occurs in the cuprates). The present context may not be
totally inappropriate for such an exploration, since it makes
contact with at least three of the many areas in which Phil
has worked, namely high-temperature superconductivity,
neutron stars (see below) and the anomalous electrostatic
effects discovered by Tao and co-workers in ordinary superconductors.3 The main question I will raise is: what would be
the novel macroscopic effects associated with such a system?
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An attempt to answer this question may perhaps give us a
new perspective on the “familiar” superconductivity which
occurs in solids.
Before addressing this question, however, a few comments
are in order. First, the idea of superconductivity occurring
in a system which by any reasonable definition is liquid is of
course itself not at all novel: it is confidently believed that in
certain regions of a neutron star not only the neutrons but
the (minority) protons may form Cooper pairs, and thus
the system would be expected to show not just superfluidity
but also superconductivity, with the usual consequences
such as magnetic vortices. Closer to home, Ashcroft and
co-workers have conjectured4 that hydrogen, when subjected
to sufficiently high pressures (~a few 100GPa) might not
only become a metallic liquid but also form Cooper pairs,
possibly of both electrons and protons, and thus exhibit
superconductivity; they have moreover raised the question
how one might identify such an anomalous superconducting
state.5 However, the attainment of such high pressures would
presumably require experimental conditions very different
from those under which the conventional superconductors
are usually studied, so that these authors do not place much
emphasis on any novel features in the gross macroscopic
behavior, but concentrate mainly on effects associated with
the coexistence of two different order parameters. Thus, as
far as I know, the question I raise here has not previously
attracted much attention in the literature.
Secondly, let’s just think for a minute about how
improbable a liquid superconductor under “near-ambient”
conditions (hereafter abbreviated ACLS to stand for Ambient
Conditions Liquid Superconductor) actually is.a To the best
of my knowledge, while there may be electrolyte solutions
which are liquid down to the highest temperature at which
superconductivity is currently known to occur (about 160K),
the lowest temperature at which any liquid metal phase is
stable under atmospheric pressure is 234K (for Hg), leaving
some distance to go. Of course, this simple comparison
may not be very meaningful. Indeed, we should consider
separately the prospects for “BCS-like” (phonon-mediated)
superconductivity and for the “exotic” (all-electronic) type.
As regards the former, while the atomic disorder characterizing the liquid state may not in itself be an impediment to
the occurrence of superconductivity (some of the highesttemperature BCS superconductors are strongly amorphous
alloys), it is not entirely clear whether the fact that the
a
After submission of the manuscript, I became aware of the paper of
P. P. Edwards et al., ChemPhysChem 7, 2015 (2006), which discusses
the possible existence of ACLS in liquid metal-ammonia solutions.
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Asia Pacific Physics Newsletter
disorder is time-dependent, with a timescale which is of
the same order as or shorter than the typical timescale for
superconductivity (Planck’s constant divided by the thermal
energy at the transition temperature) would have a strongly
inhibiting effect on the latter (note that this feature of liquid
behavior is not entirely captured by the structure of the
phonon spectrum as studied in Jaffe and Ashcroft4). My untutored guess is that it would not; however, since among the
known superconductors the ones with the highest transition
temperatures are “all-electronic”, one might prima facie think
that an ACLS would be likely to use the latter mechanism.
Here, however, there is a serious difficulty: the currently
available experimental evidence suggests that almost without
exception the order parameter in these existing materials is
anisotropic (non-s-wave). As is well known, such an order
parameter is highly vulnerable to even static disorder, let
alone the timedependent variety. Thus, all in all, the existence
of an ACLS seems rather improbable (but then, so prior to
1986 did superconductivity above 100K!).
I now turn to the main topic of this essay, namely the
novel macroscopic properties that the ACLS state might be
expected to manifest. While the discussion below is entirely
qualitative, for definiteness I shall assume that the (orders of
magnitude of) the physical parameters of the ion and electron systems are comparable to those of (say) the cuprates, so
that, for example, the superconducting condensation energy
is of the order of a few degrees K per (superconducting)
electron. For comparison, the energy associated with surface
tension should be of order 104K per (surface) atom (c.f.
below), while that required to lift an atom through 1 cm in
the earth’s gravitational field is about 1 mK. Armed with these
numbers, let us consider the likely behavior of the system
under two different kinds of experimental conditions: (a)
the ACLS (or more precisely the normal liquid metal just
above the notional onset temperature for superconductivity)
is confined to a cell or tube, with no free surface, (b) it is
contained in an open bowl or similar geometry. In contrast
to Jaffe and Ashcroft,4 I will assume throughout that pairing
occurs only in the electron system, the ions themselves
remaining throughout perfectly “normal”.
Let’s first consider case (a). In the case of the traditional
(solid) systems, superconductivity manifests itself at the
macroscopic level principally through two phenomena,
the Meissner effect and the near-infinite metastability of
circulating currents in a ring geometry (the more easily
demonstrated phenomenon of nonzero current through a
wire with zero voltage drop can be reduced, conceptually
speaking, to one or the other of these two depending on
the parameters). The Meissner effect is a thermodynamic
ARTICLES
equilibrium phenomenon, and so prima facie the only
way a difference between a standard superconductor and
an ACLS could show up would be if the ion system could
deform appreciably to give a lower-energy equilibrium state;
since compressional energies are presumably similar to
those in the standard case, this seems unlikely in the closed
geometry of case (a). So I think my prima facie expectation
would be that the ACLS would show a complete Meissner
effect in a sufficiently small external magnetic field, and also
the conventional type-II behavior in higher fields (since
there seems no obvious reason why the standard Abrikosov
vortices should not occur, with static properties similar to
the usual case).
With regard to the possibility of persistent supercurrents,
which is a metastable rather than a thermodynamic equilibrium phenomenon, the most obvious difference with a very
disordered solid alloy is that, at least over timescales long
compared to the typical ionic rearrangement time, there is
no obvious way in which any Abrikosov vortices present are
going to be pinned; hence one would expect that as soon as
the field generated by the current exceeds the lower critical
field (which is likely to be of the order of the earth’s magnetic
field) the system will transition to a resistive state. This
behaviour is not of course qualitatively different from that
of some known superconductors. However, there is a second
possible mechanism of resistance which has no analog in that
case: Consider a thin-ring geometry (transverse dimensions
of the ring smaller than the pair radius), and the nature of a
fluctuation which will allow the order parameter to slip 2π
of phase and thereby reduce the circulating supercurrent.
In the usual Langer–Ambegaokar–McCumber–Halperin
(“LAMH”) scenario6,7 the mechanism is a fluctuation to
zero of the order parameter over a length of the order of the
pair radius, with the total electron density remaining close
to constant over the whole length of the phase slip; such a
process has a cost per unit area of the order of the condensation energy times the pair radius. Any large deviation in the
total electron density, such as being driven to zero over this
or a smaller length, is strongly suppressed by the Coulomb
force. However, in an ACLS the ions may be able to move
so as to counteract this effect, and the only extra energy
involved is then that involved in the surface tension necessary
to form a thin slab of vacuum bridging the cross-section of
the ring, thereby allowing the phase slip. Given the order-ofmagnitude numbers listed above, it seems possible that this
mechanism might be competitive with the LAMH one, thus
possibly rendering unstable superflows in thin rings which
in the standard scenario would be effectively metastable. In
thicker rings the absence of a vortex pinning mechanism is
likely to have a qualitatively similar effect, cf. above.
Apart from the two fundamental manifestations of
superconductivity discussed above, the traditional systems
show a variety of other characteristics: vanishing Peltier
coefficient, Josephson effect, etc. To the extent that the leads
themselves are “conventional” normal or superconducting
materials (which the liquid ions cannot penetrate) it seems
likely that the qualitative behavior of an ACLS with respect
to such phenomena will be similar to the normal one.
Things become a lot more interesting when we consider
the “open” geometry of case (b). Those readers old enough
(like the present author) to remember playing in their
pre-OSHA (Occupational Safety and Health Administration) childhoods with droplets of mercury in the kitchen
sink will not need to be reminded that the surface tension
of metallic liquids is exceptionally high, ~1 in SI units
(which translates into the figure given above). However, it
is conceivable that this is not the only germane consideration: in particular the “Tao effect”3 may be relevant. This
effect is most naturally interpreted as showing that at least
under certain circumstances there is an extra surface energy
associated with the superconducting state. Originally, the
effect was thought to be peculiar to the cuprates, and an
explanation was developed3 in which a crucial role was
played by the strong anisotropy of these materials, a feature
which would presumably be lacking in an ACLS; however,
subsequent experiments8 suggest that it does not require
such anisotropy but is actually a generic property of the
superconducting state. To be sure, in existing experiments
the surface energy in question is small (~10−3 SI), and occurs
only in electric fields ~1kV/cm, but the mere fact that it is
not fully understood indicates a non-negligible possibility
that the surface tension of an ACLS may be anomalous even
in the context of liquid metals.
Irrespective of this (but assuming the surface tension
is not much less than that of a typical liquid metal), let us
consider how an ACLS may be expected to behave in a weak
magnetic field (such as that of the earth). A crucial difference from the case of an ordinary solid superconductor is of
course that the electron and ion systems can deform together,
thus preserving overall charge neutrality and avoiding the
activation of the strong Coulomb forces. Thus, we need to
minimize the sum of at least four and possibly five different
energies: condensation, magnetic, ordinary surface tension,
gravitational and possibly anomalous electrostatic (“Tao”)
energies. This would seem to be a rather non-trivial (and
highly geometry-dependent) problem. Were it not for the
large surface tension contribution, my gut instinct (not based
on any quantitative calculation at this stage) is that the ACLS
May 2016, Volume 5 No 2
33
ARTICLES
would spontaneously form a thin film and coat its surroundings (thereby presumably constituting a considerable safety
hazard!). Presumably, the surface tension would suppress this
behavior in its extreme form, but for a large enough sample
this effect must be overwhelmed by the terms proportional
to volume. So, if we imagine trying to conduct a standard
levitation experiment with the ACLS originally contained in
an open bowl, what will happen? Readers are invited to make
their own guesses/calculations; all I know is that I would not
like to be the environmental safety officer responsible for
developing a handling protocol for this system.
Obviously, while I have stated in this essay what I
believe to be an interesting problem, the above discussion
only scratches its surface, and is almost certainly lacking in
sufficient imagination. Indeed, I would take a large bet that
in the improbable event that an ACLS is actually realized in
the laboratory, it will rapidly turn out to have various novel
and intriguing properties not anticipated above. I heard the
story (for whose authenticity I cannot vouch) that when the
Finnish electronic giant Nokia had produced a new type
of hand-held electronic device and wanted to explore its
potential, it let loose on it a group of seven-to-nine-year-olds,
who rapidly came up with applications which their elders
had never imagined. Perhaps we should do the same with
an ACLS if it is ever realized!
Acknowledgments:
This material is based upon work supported as part of the
Center for Emergent Superconductivity, an Energy Frontier
Research Center funded by the United States Department
of Energy, Office of Science, Office of Basic Energy Sciences
under Award number DE-AC0298CH1088. I thank Cai Peng
and Tang Peizhe for helpful comments. It is a pleasure to
dedicate this essay to Phil Anderson and to wish him many
more years of happy and fruitful research in physics.
References:
1
2
3
4
34
J.K. Vonnegut, Cat’s Cradle (Delacorte Press, New
York, 1963).
A.J. Leggett and S.K. Yip, in L.P. Pitaevskii and
W.P. Halperin (Eds.), Helium-3 (North-Holland,
Amsterdam, 1990).
R. Tao, X. Zhang, X. Tang and P.W. Anderson, Formation of high-temperature superconducting balls, Phys.
Rev. Lett. 83, 5575–5578 (1999).
J.E. Jaffe and N.W. Ashcroft, Superconductivity in
liquid metallic hydrogen, Phys. Rev. B 23, 6176–6179
(1981).
Asia Pacific Physics Newsletter
5
6
7
8
E. Babaev, A. Sudbø and N.W. Ashcroft, Observability of a projected new state of matter: a metallic
superfluid, Phys. Rev. Lett. 95, 105301 (2005).
J.S. Langer and V. Ambegaokar, Intrinsic resistive
transition in narrow superconducting channels, Phys.
Rev. 164, 498–510 (1967).
D.E. McCumber and B.I. Halperin, Time scale of
intrinsic resistive fluctuations in thin superconducting
wires, Phys. Rev. B 1, 1054–1070 (1970).
R. Tao, X. Xu, Y.C. Lan and Y. Shiroyanagi, Electricfield induced formation of low temperature superconducting granular balls, Physica C 377, 357–361
(2002).
This article was originally published in PWA90: A Lifetime of Emergence (World Scientific, Singapore 2016)
ARTICLES
Einstein Versus the
Physical Review
Daniel Kennefick
Associate Professor of Physics, University of Arkansas at Fayetteville,
Editor, Einstein Papers Project, California Institute of Technology
A great scientist can benefit from peer review, even while refusing to have anything to do with it.
A
lbert Einstein had two careers as a professional
physicist, the first spent through 1933 entirely at
German-speaking universities in central Europe,
the second at the Institute for Advanced Studies in Princeton,
New Jersey, from 1933 until his death in 1955. During
the first period he generally published in German physics
journals, most famously the Annalen der Physik, where all
five of his celebrated papers of 1905 appeared.
After relocating to the US, Einstein began to publish
frequently in North American journals. Of those, the
Physical Review, then under the editorship of John Tate
(pictured in Fig. 1), was rapidly assuming the mantle of the
world’s premier journal of physics.1 Einstein first published
there in 1931 on the first of three winter visits to Caltech.
With Nathan Rosen, his first American assistant, Einstein
published two more papers in the Physical Review: the
famous 1935 paper by Einstein, Boris Podolsky, and Rosen
(EPR) and a 1936 paper that introduced the concept of
the Einstein–Rosen bridge, nowadays better known as a
wormhole. But except for a letter to the journal’s editor he
wrote in 1952—in response to a paper critical of his unified
field theory work—that 1936 paper was the last Einstein
would ever publish there.
Einstein stopped submitting work to the Physical Review
after receiving a negative critique from the journal in
response to a paper he had written with Rosen on gravitational waves later in 1936.2 That much has long been known,
at least to the editors of Einstein’s collected papers. But the
story of Einstein’s subsequent interaction with the referee
in that case is not well known to physicists outside of the
Fig. 1.
John T. Tate, circa 1930. Tate edited the Physical Review at the
University of Minnesota from 1926 until his death in 1950.
(Courtesy of the University of Minnesota Archives.)
May 2016, Volume 5 No 2
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ARTICLES
gravitational-wave community. Last March, the journal’s
current editor-in-chief, Martin Blume, and his colleagues
uncovered the journal’s logbook records from the era, a find
that has confirmed the suspicions about that referee’s identity.3 Moreover, the story raises the possibility that Einstein’s
gravitational-wave paper with Rosen may have been his only
genuine encounter with anonymous peer review. Einstein,
who reacted angrily to the referee report, would have been
well advised to pay more attention to its criticisms, which
proved to be valid.
Doubting gravitational waves
Einstein introduced gravitational waves into his theory of
general relativity in 1916, within a few months of finding
the correct form of the field equations for it. Although the
concept of gravitational radiation was then relatively new and
no experimental evidence existed to support it, the analogy
with the case of the electromagnetic field was so compelling
that by the 1930s most scientists thought that gravitational
waves must exist in principle. Nevertheless, in 1936 Einstein
wrote to his friend Max Born:
Together with a young collaborator, I arrived at the
interesting result that gravitational waves do not
exist, though they had been assumed a certainty
to the first approximation. This shows that the
non-linear general relativistic field equations can
tell us more or, rather, limit us more than we have
believed up to now.4
Einstein submitted this research to the Physical Review
under the title “Do Gravitational Waves Exist?” with Rosen
as coauthor. Although the original version of the paper no
longer exists, Einstein’s answer to the title question, to judge
from his letter to Born, was “No.” It is remarkable that at
this stage in his career Einstein was prepared to believe that
gravitational waves did not exist, but he also managed to
convince his new assistant, Leopold Infeld, who replaced
Rosen in 1936, that his argument was valid.5
But not everyone was so easily convinced. The Physical
Review received Einstein’s submission on 1 June 1936,
according to the journal’s logbook. Tate returned the
manuscript to Einstein on 23 July with a critical review and
the mild request that he “would be glad to have [Einstein’s]
reaction to the various comments and criticisms the referee
has made.” Einstein wrote back on 27 July in high dudgeon,
withdrawing the paper and dismissing out of hand the
referee’s comments:
36
Asia Pacific Physics Newsletter
Dear Sir,
We (Mr. Rosen and I) had sent you our manuscript for publication and had not authorized you
to show it to specialists before it is printed. I see
no reason to address the—in any case erroneous—
comments of your anonymous expert. On the
basis of this incident I prefer to publish the paper
elsewhere.
Respectfully,
P.S. Mr. Rosen, who has left for the Soviet Union,
has authorized me to represent him in this matter.
On 30 July, Tate replied that he regretted Einstein’s decision to withdraw the paper, but stated that he would not set
aside the journal’s review procedure. In particular, he wrote,
“I could not accept for publication in THE PHYSICAL
REVIEW a paper which the author was unwilling I should
show to our Editorial Board before publication.”
The paper was, however, subsequently accepted for publication by the Journal of the Franklin Institute in Philadelphia,6
a periodical in which Einstein had already published. The
paper appeared with radically altered conclusions in early
1937. Aletter dated 13 November 1936, from Einstein to the
journal’s editor, indicates that the institute had accepted the
paper in its original form: Einstein simply explained why
“fundamental” changes in the paper were required because
the “consequences” of the equations derived in the paper had
previously been incorrectly inferred.
What originally led Einstein to the conclusion that
gravitational waves do not exist? Having set out to find an
exact solution for plane gravitational waves, he and Rosen
found themselves unable to do so without introducing
singularities into the components of the metric that describes
the waves. This was surely not at all what they had hoped for.
But, like good physicists confronted with the unexpected,
they attempted to turn it to their advantage. In fact, they
felt they could show that no regular periodic wavelike solutions to the equations were possible.7 Instead of a solution
to the Einstein equations, they had a nonexistence proof
for solutions representing gravitational waves— a far more
important and breathtaking result.
Today it is well known that one cannot construct a single
coordinate system to describe plane gravitational waves
without encountering a singularity somewhere in spacetime.
But it is also understood that such a singularity is merely
apparent and not real. It is a coordinate singularity, analogous
to the problem one encounters when attempting to find the
longitude of the North Pole. Einstein was one of the first
ARTICLES
to understand the critical difference between coordinate
and physical singularities, but in the 1930s there was still
no mathematical formalism for distinguishing between the
two. It was something that had to be worked out by trial and,
frequently, error. Only after World War II did the identification of singularities become rigorous. In 1936 Einstein and
Rosen were too cautious, treating a harmless coordinate
effect as a real physical pathology. It simply did not occur to
them that trying to cover the whole of their spacetime with
a single coordinate system was asking too much.
Chance meeting
In the summer of 1936, the relativist Howard Percy
Robertson (pictured in Fig. 2) returned to Princeton from
a sabbatical in Pasadena, and later that year struck up a
friendship with Einstein’s then newly arrived assistant Infeld.
One of the most distinguished figures in the new field of
cosmology, Robertson was a colorful, jovial character who
enjoyed cultivating enemies as much as he, in Infeld’s words,
“enjoyed spiteful gossip” about his colleagues.
He told Infeld that he did not believe Einstein’s result, and
his skepticism was unshakable. Robertson went over Infeld’s
version of the argument with him, and they discovered
an error.5 Infeld related the conversation to Einstein, who
Fig. 2.
Howard Percy Robertson (1903–1961).
(Courtesy of AIP Emilio Segrè Visual Archives, PHYSICS TODAY Collection.)
concurred and drastically changed the Franklin Institute
paper in proofs.
Robertson had uncovered an error in his (Infeld’s) version
of the proof, Einstein replied that he had coincidentally
and independently uncovered an error in his own proof the
night before.5 Unfortunately Infeld gives no details about
those errors in his autobiography. He writes that Einstein
had only realized that his proof was incorrect and had still
not managed to find the gravitational wave solution he had
been looking for.
But Einstein had been closer to a solution than he thought
and it was here that Robertson made his key contribution,
at least according to remarks made by Rosen in a later paper
of 1955.8 Robertson observed that the singularity could be
dealt with by a change of coordinates, an approach that
revealed that Einstein and Rosen were dealing with a solution
representing cylindrical waves. With the coordinate change
the worrisome singularities were relegated to the central axis
of the spacetime, where one would expect to find the source
of the cylindrical waves.
Associating singularities with a material source was
relatively common and widely accepted, although Einstein
and some others had often expressed serious reservations
about the practice. But any port in a storm will do, and
Einstein was happy to retitle his paper “On Gravitational
Waves,” and present those cylindrical waves, which he had
stumbled upon unwittingly.
The irony, of course, is that Einstein could have found that
escape route months earlier, simply by reading the referee’s
report that he had dismissed so hastily. The referee had also
observed that casting the Einstein–Rosen metric (as we now
call this solution of the Einstein equations) in cylindrical
coordinates removes the apparent difficulty.
Coincidentally, in the Soviet Union, Rosen was also
having second thoughts, and wrote back to Einstein that he,
too, thought there was an error in the paper. But Rosen was
not completely happy with the Franklin Institute version, so
in 1937 he published his own revised treatment—one that
proves only the nonexistence of plane gravitational waves—
in a Soviet journal.7 That paper is the closest account we have
to the original manuscript submitted to the Physical Review.
After the war, Ivor Robinson, Hermann Bondi, and Felix
Pirani showed that Rosen’s argument was incorrect because
the singularities involved were merely coordinate in nature.
Meanwhile, Einstein was not a man to waste time on
embarrassment. Infeld relates the amusing detail that
Einstein was due to give a lecture in Princeton on his new
nonexistence proof, just one day after his discovery of its
errors. He had not yet spoken to Robertson and discovered
May 2016, Volume 5 No 2
37
ARTICLES
the way out of his difficulty, and so was obliged to lecture
on the invalidity of his own proof. He concluded the talk by
saying “If you ask me whether there are gravitational waves
or not, I must answer that I do not know. But it is a highly
interesting problem.”5
Einstein rarely let personal pride interfere with his work.
While they were working on the popular book, Evolution of
Physics: The Growth of Ideas from Early Concepts to Relativity
and Quanta, which they wrote together, Infeld told Einstein
that he took special care because he could not “forget that
your name will appear on it.”
Einstein laughed his loud laugh and replied:
‘You don’t need to be so careful about this. There
are incorrect papers under my name too.’5
Referees and precedents
Although it now bears Einstein and Rosen’s names, the solution for cylindrical gravitational waves had been previously
published by the Austrian physicist Guido Beck in 1925. But
Beck’s paper was completely unknown to relativists with the
single exception of his student Peter Havas, who entered
the field in the late 1950s. In a 1926 paper by the English
mathematicians O. R. Baldwin and George B. Jeffery, and in
the referee’s report on Einstein’s paper, there was discussion
of the fact that singularities in the metric coefficients are
unavoidable when describing plane waves with infinite
wavefronts. But although such a wave shows some distortion,
in the words of the referee, “the field itself is flat” at infinity.9
Clearly, the referee’s familiarity with the literature
exceeded Einstein’s, but then Einstein was notoriously lax in
that regard. The published Einstein–Rosen paper contains no
direct reference to any other paper whatsoever and only two
other authors are even mentioned by name. In response to
Infeld’s suggestion that he search the literature for previous
work, Einstein laughed and said, “Oh yes. Do it by all means.
Already I have sinned too often in this respect.”5
So who was the referee? The report is 10 pages long and
shows a deep, if not total, familiarity with the literature on
gravitational waves; the referee knew of the 1926 paper
by Baldwin and Jeffery, but not Beck’s of 1925. The copy
forwarded to Einstein was typewritten and the spelling
followed American practices. That points to an American
author with a strong interest in general relativity. Few people
at the time—among them Robert Oppenheimer and Richard
Chase Tolman, both based in California—fit that description.
Suspicion naturally falls on Robertson too, of course. After
all, he appeared to have the solution to the paper’s flaws at
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Asia Pacific Physics Newsletter
his fingertips in the fall of 1936 when he spoke with Infeld.
In the first half of 1936, Robertson was on sabbatical
at Caltech, and therefore absent from Princeton when the
gravitational-wave paper was presumably written. (Rosen
did not leave for the Soviet Union until near the end of July,
according to a letter written on his behalf by Einstein to
Vyacheslav Molotov on 4 July.) Robertson apparently did
not return to Princeton until mid-August. Einstein was on
vacation in upstate New York until late August; the angry
letter to Tate, dated 27 July, was sent from Saranac Lake.
Therefore Robertson’s encounter with Infeld, which probably
took place in early October, may have been his first opening
to approach the great man in person about the difficulties
with his paper.
Robertson’s own papers are preserved in the Caltech
archives. Among them, when I first browsed the collection
ten years ago, was a letter to Tate, written on 18 February
1937. Robertson writes,
You neglected to keep me informed on the paper
submitted last summer by your most distinguished
contributor. But I shall nevertheless let you in
on the subsequent history. It was sent (without
even the correction of one or two numerical slips
pointed out by your referee) to another journal, and
when it came back in galley proofs was completely
revised because I had been able to convince him in
the meantime that it proved the opposite of what
he thought.
You might be interested in looking up an article
in the Journal of the Franklin Institute, January
1937, p. 43, and comparing the conclusions reached
with your referee’s criticisms.
Therefore, it seems clear that Robertson was the referee.
Finding that Einstein had completely ignored his written
critique, he took the opportunity of their collegial closeness
at Princeton to correct the great man in a less confrontational
fashion. Blume’s release of the logbook records—a decision
made because 69 years have passed and no one involved is
still living—confirms the identity (see Fig. 3).
Inspired by this discovery, I returned to the Robertson
archives to check on his movements that summer. To my
surprise, further material had been added to the archive:
Sitting in the middle of the Tate correspondence was most
of the immediate exchange between Robertson and Tate
concerning the Einstein–Rosen manuscript. Here is what
Robertson had to say in his reply (dated 14 July) to Tate’s
still-missing original letter:
ARTICLES
Fig. 3.
An early extract from the Physical Review logbook. The Einstein–Rosen article was received by the journal on 1 June 1936. After a delay
of more than a month, John Tate sent a referral to Howard Percy Robertson on 6 July, finding him in Moscow, Idaho, on vacation after a sabbatical at
Caltech. Robertson returned the manuscript and his review to Tate on 17 July. Six days later the package was sent back to Einstein.
(Courtesy of Martin Blume, American Physical Society.)
Dear Tate:
Well, this is a job! If Einstein and Rosen can establish their case, this would constitute a most important criticism of the general theory of relativity. But
I have gone over the whole thing with a fine-tooth
comb (mainly for the sake of my own soul!), and
can’t for the life of me see that they have established
it. It has long been known that there are difficulties
in attempting to treat infinite plane gravitational
disturbances in general relativity—even in the
classical theory the potential acts up at infinity in
such cases—and as far as I can see the additional,
much more serious, objections of Einstein and
Rosen do not exist. I can only recommend that you
submit my criticisms to them for their consideration, and with this in mind I have written up in
duplicate a series of “Comments” which you can,
if you are so minded, send them. The alternative
would be to publish it as it stands, taking account
only of Comments (a) and (b) which deal with
typographical errors of a minor sort. Such a paper
would be certain to give rise to a lot of work in
this field of gravitational waves, which might be
a good thing—provided they didn’t flood you out
of house and home.
Tate thanked Robertson and rewarded his diligent
referee in the usual manner—by sending him another tricky
assignment.
Early journal policies
We are probably justified in assuming that Einstein, overcome with the novelty of receiving such a report, barely
glanced at the 10-page set of referee comments he was sent.
German journals in the early part of the 20th century were
considerably less fastidious than the Physical Review about
what they published. Infeld claimed that the German attitude,
in contrast to that prevailing in Britain and America, was
“better a wrong paper than no paper at all.”5 In a March
1936 letter to Einstein, the relativist and fellow European
exile Cornelius Lanczos, who had himself been on the
receiving end of one of Robertson’s reports, remarked on “the
rigorous criticism common for American journals” such as
the Physical Review.10
Historians Christa Jungnickel and Russel McCormmach
have studied in some detail the editorial policies of Annalen
der Physik, the leading German journal of the early 1900s,
and note that “the rejection rate of the journal was remarkably low, no higher than five or ten percent.”11 They describe
the editors’ reluctance to reject papers from established
physicists, even relatively junior ones. As they put it, “Now
and then the journal published bad papers by good physicists.” In one specific example, editor Paul Drude annoyed
Max Planck by printing what Planck considered a worthless
paper, whose author had “appealed to [Drude] personally,
and Drude lacked the heart to refuse him.”11
Planck’s own editorial philosophy was to “shun much
more the reproach of having suppressed strange opinions
than that of having been too gentle in evaluating them.”10 In
America things were different, although Robertson and Tate
surely treated Einstein more gently than they would have
many others. Indeed, Robertson, in his very next report to
Tate, commented that the author “is a man of good scientific
standing, and it would seem to me that if he insists, he has
more right to be heard than any single referee has to throttle!”
That dispute turned more on matters of interpretation,
though, and when it came to a paper that might actually be
May 2016, Volume 5 No 2
39
ARTICLES
wrong, even an Einstein had to be queried, however gently.
Doubtless the rigorous criticism may have come as
something of a shock to Einstein, who was accustomed to
gentler treatment early in his career. However, Einstein could
be very frank and direct in his criticism of others’ work. From
1914 on, as a member of the Prussian Academy of Sciences,
he was regularly called on to review articles submitted to
the academy’s proceedings. The German word for worthless
frequently occurs in those brief reviews. As a member of the
academy, Einstein had his papers published without question or revision. Anything less must have seemed to him a
tremendous slight.
In his letter to Einstein, Tate had carefully avoided stating
that anonymous review by the editorial board or others was a
necessary step in the acceptance of a paper by the journal. In
fact, the Physical Review logbook suggests that neither of the
two previous papers by Einstein and Rosen, including the one
with Podolsky, had been sent to a referee: In both cases the
field for the referee’s name was left blank, and the EPR paper
was sent for publication the day after its receipt at the journal.
Therefore it is likely that the gravitational wave paper was
Einstein’s first encounter with the anonymous peer-review
system practiced in American journals at the time.
That Tate chose to have the 1936 paper refereed is interesting. After all, Einstein’s two previous submissions were
certainly controversial. EPR is arguably the most controversial paper Einstein ever published, and the Einstein–Rosen
bridge paper was part of an ongoing controversy with Ludwig
Silberstein. 10 Einstein and Rosen’s letter to the Physical
Review in 1935 was part of this same debate. Tate published
both of those papers without outside advice.
A paper purporting to prove that gravitational waves
did not exist, though, apparently sounded alarms with him.
Nowadays one imagines that most physicists of the time
knew little and cared even less about general relativity. But
apparently gravitational waves were already such a wellaccepted prediction of the theory, despite the absence of
experimental support, that such a surprising result warranted
some scrutiny. More than a month elapsed between receipt
of the paper and its referral to Robertson. The delay certainly
suggests hesitation on Tate’s part, and may even be evidence
of an initial round of editorial discussion.
In general Tate did not like to slow the publication
of important work and often relied on his own editorial
instincts, 12 which certainly served Einstein well. Tate
published the better-known papers expeditiously and, by
consulting Robertson for the third, saved Einstein from
what would have been a very public embarrassment. The
relatively innocuous Franklin Institute paper still attracted
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Asia Pacific Physics Newsletter
newspaper attention. Indeed, Rosen learned that the paper
had appeared only when he received a newspaper clipping
about it from a friend. The price for Tate was that he would
never again receive a submission from “his most distinguished contributor.”
Special thanks go to Martin Blume and the Physical Review for
permission to see and publish the critical line and details from the
logbook. Also thanks to Diana Buchwald for translation of Einstein’s
letter to Tate, and to John T. Tate Jr for permission to quote from his
father’s correspondence. I am grateful to the Caltech Archives for
permission to quote from the correspondence of H. P. Robertson and
to the Hebrew University of Jerusalem for permission to quote from
Einstein’s correspondence.
References:
1
2
3
4
5
6
7
8
9
10
11
12
A. Pais, in The Physical Review: The First Hundred
Years, H. H. Stoke, ed., AIP Press, New York (1995),
p. 1.
A. Pais, “Subtle is the Lord”: The Science and Life of
Albert Einstein, Oxford U. Press, New York (1982), p.
494.
D. Kennefick, in The Expanding Worlds of General
Relativity, H. Goenner, J. Renn, J. Ritter, T. Sauer, eds.,
Birkhäuser-Verlag, Boston (1999), p. 207.
A. Einstein, The Born–Einstein Letters: Friendship,
Politics, and Physics in Uncertain Times, MacMillan,
New York (2005), p. 122.
L. Infeld, Quest: An Autobiography, Chelsea, New York
(1980).
A. Einstein, N. Rosen, J. Franklin Inst. 223, 43 (1937).
N. Rosen, Phys. Z. Sowjetunion 12, 366 (1937).
N. Rosen, in Jubilee of Relativity Theory, A. Mercier, M.
Kervaire, eds., Birkhäuser-Verlag, Basel, Switzerland
(1956), p. 171.
G. Beck, Z. Phys. 33, 713 (1925); O. R. Baldwin, G. B.
Jeffery, Proc. Phys. Soc. London, Sect. A 111, 95 (1926).
P. Havas, in The Attraction of Gravitation: New Studies
in the History of General Relativity, J. Earman, M.
Janssen, J. Norton, eds., Birkhäuser-Verlag, Boston
(1993).
C. Jungnickel, R. McCormmach, Intellectual Mastery
of Nature: Theoretical Physics from Ohm to Einstein,
vol. 2, U. of Chicago Press, Chicago (1986), p. 309.
A. O. C. Nier, J. H. Van Vleck, in Biographical Memoirs,
vol. 47, National Academies Press, Washington, DC
(1975), p. 461.
Reproduced with permission from Phys. Today. Copyright 2005, AIP
Publishing LLC. (http://dx.doi.org/10.1063/1.2117822)
ARTICLES
Reflections on the Discovery of
Einstein’s Gravitational Wave
Da Hsuan Feng
Director of Global Affairs and Special Advisor to Rector, University of Macau,
Fellow of the American Physical Society
O
n January 11, 2016, in a news conference held in
Washington D. C., it was announced that after
nearly two decades of arduous work, the gravitational wave proposed by Einstein a century ago was detected
by the Laser Interferometer Gravitational-Wave Observatory
(LIGO.) In today’s “flat world,” this major scientific observation also created a ripple in Hong Kong and Macau at the
end of the globe. On January 12 and January 19, Professor
Tjonnie G. F. LI presented to the Physics Department of the
Chinese University of Hong Kong (CUHK) in Cantonese
and English, respectively. On January 20, the University of
Macau invited Mr. Chon-Fai Kam, a native of Macau and
a PhD. candidate in theoretical physics of CUHK to also
present a discussion to the university community at-large.
The title of Mr. Kam’s talk is “Einstein’s Gravitational Ripple:
The Conquer of a Century.” Due to the great timeliness of
the subject, the University of Macau made a special effort to
bring the notice of this presentation to the attention of the
secondary schools in Macau.
The instant reaction of Hong Kong and Macau at the
other end of the globe made me thought of the reaction of
another great event in 1957 in Singapore. That year, I was in
my fifth grade in elementary school. In October, I read in the
Chinese newspaper a report that two Chinese, Tsung-Dao
Lee and Chen-Ning Yang, received “something something”
high accolade. I remember vividly in the newspaper showed a
picture of Tsung-Dao Lee, standing in front of a blackboard.
On the board there were characters that looked like squiggles
of some sort!
I remember that I was quite excited by the report. The
reason for my excitement was not because Lee and Yang won
the physics Nobel Prize. After all, at that point in my life, I
neither knew what physics was, not what the Nobel Prize
meant! I was excited because “just like me,” Lee and Yang
were Chinese! Of course, in hindsight, the “just like me” was
very much an over stretched of the imagination!
However, as soon as my excitement subsided, what
happened subsequently was a string of disappointments.
One of the disappointments was because I knew nothing
about the great achievements of these two gentlemen. The
next disappointment was whomever I asked, I could not get
a clear answer, or any answer at all. As an elementary school
student, I considered students in Junior High School or
Senior School surely possessing a great deal of knowledge.
Yet I soon discovered that those I knew in Junior and Senior
High Schools knew no more than me, which was nothing.
At that time in Singapore, there were two institutions of
higher learning, the newly created Nanyang University and
the University of Singapore. As far as I could recall, neither
made any effort to publicly explain the greatness of Lee and
Yang! Eventually, I came to the conclusion that “good things
cannot happen here!” This is what I refer to nowadays as a
“third word mentality!”
The reaction in Hong Kong and Macau to the discovery
of the gravitational wave is indeed a strong contrast to the
reaction to Lee and Yang nearly sixty years ago. Today, I can
easily imagine that no bewilderment will bestow a fifth grade
student. After all, he/she could go online, could ask his/her
classmates, parents, even his/her teachers. Worse come to
worst, he/she could even go to and be welcome by CUHK
or the University of Macau to attend the public lectures on
this great discovery! In his/her mind, there is no room where
“the third world mentality” could hide!
In recent years, I have often given lectures where I explicitly mentioned that nurturing the “inherent self-confidence”
of Asian youth is an important, if not the only mission of
education. From this perspective, while it is obviously a
good deed that the University of Macau rapidly reacted
to the announcement of the discovery of the gravitational
wave, but it is even more important that as a university, it
deems assistance to youngsters to develop “inherent selfconfidence” as fundamental. To me, allowing “good things
can happen here” is an important step in instilling “inherent
self-confidence!”
May 2016, Volume 5 No 2
41
NEWS
Recent News from the Overseas
Chinese Physics Association
Albert Chang
OCPA President
Duke University
2016 APS March Meeting FIP (Forum on International Physics) Reception and the OCPA Awards
Ceremony
The FIP reception, which took place Tuesday, March 15, from
6:00 - 8:00 pm, in the Baltimore Hilton, was a great success
attended by over 60 international participants. Representatives of the OCPA, including Prof Dongping Zhong (Ohio
State; OCPA Secretary) and Prof Xuan Gao (Case Western;
OCPA Vice Chair Communication Committee) were in
attendance. Several international organizations spoke and
presented awards, after which Dr Amy Flatten (APS Director
of International Affairs) spoke about the mission and
activities of the APS FIP. In addition to OCPA, the Korean
Society and the Iranian Society also spoke. There was also
a sizable contingent of Turkish participants. It was truly an
international gathering.
Regarding OCPA and its constituency, several ethnic
Chinese physicists based outside of the USA and Canada
were elected 2015 APS Fellows. The full list, as well as those
from the US and Canada, is available on the OCPAWEB site
(http://ocpaweb.org/home/2015-aps-fellows/). In particular,
Prof. Yugang Ma (SINAP, Shanghai) was on hand to receive
his fellowship certificate and pin (please see photo).
During the OCPA Awards ceremony, I spoke about the
mission and main activities of the OCPA, as well as the
upcoming OCPA9 conference in Beijing (July 17-20, 2017
with a High School Program on July 16). I invited all to come
to Beijing. In addition, I spoke on our goal to connect with
international physics and astronomy organizations.
The OCPA Award winners were all in attendance to
receive their award plaques and checks. These included
OYRA (Macronix Prize) winners, Prof Lu Li (Michigan)
and Prof David Shih (Rutgers), and AAA (Robert T. Poe
Prize) winners, Prof Yu-Gang Ma (SINAP) and Prof QingFeng Sun (PKU). Please see attached photos, courtesy Prof
Dongping Zhong.
From right: Amy Flatten (Director of International Affairs, APS), Albert M. Chang (President.
OCPA), Young-Kee Kim (President, Association of Korean Physicists in America), and Farbod
Shafiei (President, Iranian-American Physicists Group Network).
42
Asia Pacific Physics Newsletter
Yugang Ma receiving his 2015 APS Fellow certificate
from the reception host, Young-Kee Kim (U Chicago;
President, Association of Korean Physicists in
America).
NEWS
2015 APS Prize Winners
Earlier, we announced the winners of the 2016 APS Prizes.
OCPA Outstanding Young Researcher Award OYRA
(Macronix Prize) winner Lu Li receiving his Award from
OCPA President Albert Chang.
OCPA Outstanding Young Researcher Award OYRA
(Macronix Prize) winner David Shih receiving his Award
from OCPA President Albert Chang.
OCPA Achievement in Asia Award AAA (Robert T. Poe
Prize) winner Yu-Gang Ma receiving his award from
OCPA President Albert Chang.
1) 2016 Herman Feshbach Prize in Theoretical Nuclear Physics
Recipient: Xiangdong Ji, University of Maryland, College Park and Shanghai
Jiao Tong University, for pioneering work in developing tools to characterize
the structure of the nucleon within QCD and for showing how its properties
can be probed through experiments; this work not only illuminates the
nucleon theoretically but also acts as a driver of experimental programs
worldwide.
2) 2016 Tom W. Bonner Prize in Nuclear Physics Recipient: I-yang Lee,
Lawrence Berkeley National Laboratory, for seminal contributions to the
field of nuclear structure through the development of advanced gamma-ray
detectors as realized in the Gammasphere device, and for pioneering work
on gamma-ray energy tracking detectors demonstrated by the Gamma-ray
Energy Tracking Array(GRETINA).
3) 2015 Carl E. Anderson Division of Laser Science Dissertation
Award Recipient: Yang Zhao, Stanford University, for her thesis entitled
"Bio-Inspired Nanophotonics: Manipulating Light at the Nanoscale with
Plasmonic Metamaterials."
4) 2015 Outstanding Doctoral Thesis Research in Atomic, Molecular,
or Optical Physics Recipient Norman Yao, Harvard University, for
"Topology, Localization, and Quantum Information in Atomic, Molecular
and Optical Systems."
5) 2015 Award for Outstanding Doctoral Thesis Research in
Biological Physics Recipient Quan Wang, Stanford University, for his
thesis "Enabling multivariate investigation of single-molecule dynamics in
solution by counteracting Brownian motion."
6) 2016 Dissertation Award in Nuclear Physics Recipient Chun Shen,
McGill University, for his successful prediction of anisotropic flow in Pb+Pb
collisions at the LHC, his elucidation of the `direct photon flow puzzle', and
his contributions to the development of a computational tool of viscous
fluid dynamics enabling precision studies of relativistic heavy-ion collisions.
7) 2015 M. Hildred Blewett Fellowship Recipient: Huey-Wen Lin,
UC-Berkeley. Huey-Wen Lin is a visiting assistant professor at the University
of California, Berkeley. She conducts research in particle and nuclear theory
and is investigating properties of hadrons to provide Standard Model inputs
to searches for physics beyond the Standard Model. The Blewett Fellowship
will enable Lin to continue her research and publish papers using the data
accumulated during the years prior to her break, with the goal of getting back
on the academic tenure track. She will also access supercomputing facilities
to improve results and explore connections with other physics subfields.
OCPA Achievement in Asia Award AAA (Robert T. Poe
Prize) winner Qing-Feng Sun receiving his Award from
OCPA President Albert Chang.
May 2016, Volume 5 No 2
43
NEWS
Celebration of the 50th Anniversary of
the “Rencontres de Moriond”
International Workshop on
“Fundamental Science and Society”
ICISE, Quy Nhon, Vietnam, 7-8 July 2016
O
n the occasion of the 50th anniversary of the
prestigious “Rencontres de Moriond”, the Ministry
for science and technology of Vietnam, the Popular
Committee of the Province of Binh Dinh, the “Rencontres du
Vietnam” and the “Rencontres de Moriond” are organizing a
workshop on the theme “Fundamental Science and Society”,
with the high patronage of UNESCO and the support and
labels of the International Solvay Institutes and CERN. The
workshop benefits from the sponsorship of H.E. Vu Duc
Dam, Vice Prime minister and H.E. Chu Ngoc Anh and
Nguyen Quân, Minister and Former Minister of Science and
Technology of Vietnam. The two-day event will take place in
Vietnam, at the new International Conference Center in Quy
Nhon, during the first week of July 2016 (7 and 8 of July).
The “Rencontres de Moriond” have played an instrumental role in the development of High Energy Physics in
the last 50 years. The new International Conference Center
in Quy Nhon, where their sister activity “Rencontres du
Vietnam” take place, constitutes a focal intellectual center
in South-East Asia devoted to high-level education and
curiosity-driven research, in the heart of one of the most
dynamical and future-oriented regions on the planet.
The topics addressed by the workshop are relevant to all
fundamental sciences. This will be reflected in the invitation of leading figures not only from physics, but also from
mathematics, economics, chemistry and biology.
Two important ideas would be emphasized:
• Fundamental science transforms our world with
the changes it brings, and its impact on the technological
revolutions such as electronics, lasers, web…, on sustainable
development in green chemistry, understanding climate
change, energy, and on health, e.g. genetics, imaging…, and
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Asia Pacific Physics Newsletter
on all societal applications which originate from it, such as
cellular phones, GPS…
• Fundamental science – and large projects in particular
– is organized around societal models which are based on
collaboration and competition (“coopetition”), open mindedness, sharing and friendship among peoples, of which
one brilliant example is CERN, but also the Rencontres de
Moriond. These models are relevant to developed societies
which tend to isolate themselves in individualism, relativism,
even sectarianism, but also to developing societies, because
they participate in this development, contribute to peace and
to common values, the bases for humanity.
The workshop will be structured around round tables
addressing various historical, current and future issues
relevant to fundamental science and society, with an opening
up towards Asian countries, in particular towards developing
countries around Vietnam and the themes proper to them.
Prof Jean Tran Thanh Van with late Nobel Laureate Prof Abdus Salam.
NEWS
High-level representatives of the Vietnamese government
have confirmed their participation in the inaugural session.
This event will be an opportunity for scientists to interact
with decisions makers and representative of private economy.
http://rencontresduvietnam.org/conferences/2016/
fundamental-science-and-society/
The conference will be organized at the International
Center for Interdisciplinary Science and Education in
Vietnam (ICISE) by Rencontres du Vietnam, a scientific
non-profit organization. The venue is located at a beautiful
beach in Vietnam, thus allowing participants also to enjoy
the nature, culture while having rich scientific discussion.
The conference will be followed by the "Particles, Strings and
Cosmology" (PASCOS 2016).
The International Centre for Interdisciplinary Science
Education (ICISE) in the city of Quy Nhon (Central
Vietnam) has the ambitious objective to focus on developing
science and education, helping young Asian students and
scientists to meet with the international science community,
bringing the opportunity to accelerate their knowledge by
attending lectures and sharing ideas with overseas high-level
counterparts.
The International Centre for Interdisciplinary Science Education (ICISE) in Quy Nhon , Vietnam.
Map of Qui Nhon and ICISE
General view of the ICISE Center
May 2016, Volume 5 No 2
45
NEWS
Rare Astronomical Event: Partial
Solar Eclipse Observation in NUS
Cindy Ng
Director of the IPS-NUS Solar Eclipse Event
Abel Yang
Deputy Director of the IPS-NUS Solar Eclipse Event
Phil Chan
Solar Event Advisor and Deputy Head (Resource) of NUS Physics Department
T
he Institute of Physics, Singapore (IPS) and the
National University of Singapore (NUS) Department
of Physics organised a Solar Eclipse Event at NUS
football field from 8th (evening) to 9th (morning) March
2016. This spectacular astronomical phenomenon (a partial
solar eclipse) with an obscuration of almost 90% was visible
in Singapore on the morning of 9th March. It started at
7:22am on 9 March, reaching 87% obscuration at 8:23 am.
Solar eclipses occur when the Moon moves in between
the Sun and Earth, casting a shadow on the Earth's surface.
This year, the major eclipse occured in South East Asia
which is certainly a rarity in this part of the world. The 9th
March eclipse was more spectacular than the one observed
in Singapore seven years ago, in 2009 (slightly above 80%
obscuration).
Two NUS physics students sponsored by the NUS Physics
department, Ms Laurentcia Arlany and Mr Edmund Yuen,
took 3 flights to Luwuk (Sulawesi) Indonesia on an expedition led by a well-known local astronomer Mr Michael
Mathews to observe the total solar eclipse. The main objective is to look for shifts of stars’ positions during the Total
Solar Eclipse there by verifying Einstein’s General Relativity
Theory. Incidentally, this year is the 101st anniversary of the
discovery of the Theory of General Relativity. This exercise
of looking for the shifts in stars’ positions is supervised by
NUS dons, Dr Abel Yang and Assoc. Prof Phil Chan, and is
the first of its kind done by local astronomers.
Mr Mathews filmed the solar eclipse and also telecast
the eclipse “LIVE” to the NUS football field directly from
Sulawesi. More than 3,000 people watched the Partial Eclipse
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Asia Pacific Physics Newsletter
Teachers at the astrophotography exhibition.
NUS staff and students, as well as members of the public, attended the
public lectures on solar eclipse, safe solar observation and solar imaging.
NEWS
More than 3000 participants waited in anticipation to witness this rare
phenomenon.
and watched the live telecast from Indonesia at the NUS
football field. Ms Laurentcia remarked, "Seeing a total solar
eclipse is a rare opportunity. It is a different view from what
people see in Singapore, which is only partial."
The two-day IPS-NUS event led by Dr Cindy Ng started
on the eve of the solar eclipse with public lectures explaining
the solar eclipse, safe solar observation and solar imaging.
The speakers were Assoc. Prof Phil Chan, Mr Alfred Tan
(Vice Principal of Paya Lebar Methodist Girls' School and
a renowned solar amateur astronomer), and Mr Grey Tan,
one of the founders of “TinyMOS”. “TinyMOS” is a start-up
by NUS students that launched Tiny1, the first-ever portable
astrophotography camera which can capture barely-visible
celestial objects with an exposure of approximately 30
seconds and offers a live preview for locating constellations
and stars.
There was also an overnight star-gazing session at the
football field. Students from the Department of Physics,
the Special Programme in Science (SPS) and the NUS
Astronomical Society (NUSAS) set up telescopes to observe
the celestial highlights of the night.
Many well-known local amateur astronomers namely,
Mr James Ling, Mr Remus Chua, Mr Kelvin Ng, and Mr Pan
Junwei were invited to share their expertise. NUSAS also held
a Messier Marathon, their first-ever attempt to find as many
Messier objects as possible during one night in Singapore.
Messier objects are a set of over 100 astronomical objects
first listed by French astronomer and comet hunter Charles
Messier in 1771.
The Science Faculty also organised a two-day astrophotography exhibition, featuring the works of Mr Remus
Chua (former NUS research scholar and renowned astrophotographer), Dr Abel Yang, and Astrophysics students
from the NUS Observatory.
Watching the live telecast of the total solar eclipse live telecasted from
Sulawesi, Indonesia. Participants were filled with excitement as they
observed the peak of the solar eclipse as it reached 100% obscuration.
Well-known local amateur astronomer, Mr James Ling’s giant refractor is
one of the main attractions at the NUS Solar Eclipse.
Taken at Luwuk (Sulawesi) Indonesia by Ms Laurentcia Arlany (MSc
particle physics) & Mr Edmund Yuen (Astrophysics undergraduate) from
the NUS Astro and Particle Physics group, Solar Eclipse 2016.
May 2016, Volume 5 No 2
47
NEWS
Turing Prize Winner
Prof Andrew Chi-Chih Yao Explores
Development of Quantum Computing
at HKUST 25th Anniversary Distinguished Speakers Series
T
he Hong Kong University of Science and Technology
(HKUST) hosted the 25th Anniversary Distinguished
Speakers Series on 28 January, featuring Prof Andrew
Chi-Chih Yao, the only Chinese Turing Prize winner.
In his talk titled “Quantum Computing: A Great Science
in the Making”, Prof Yao told the audience the secrets in the
atoms that could potentially unleash the enormous power
of quantum computing. He also delved into the advantages
of quantum computing and shared his insights into how it
will revolutionize information processing.
“Quantum computer comes at a fortuitous time when
the Moore’s law for computing is starting to reach its
physical limit imposed by quantum mechanics. The design of
quantum computer offers a daring approach: to take advantage of the quantum problem instead of fighting it,” he said.
Prof Yao received his Bachelor of Science in Physics from
Taiwan University in 1967, PhD in Physics from Harvard
University in 1972, and PhD in Computer Science from the
University of Illinois in 1975. From 1975 onward, he served
on the faculty at Massachusetts Institute of Technology,
Stanford University, University of California in Berkeley
and Princeton University. In 2004, he joined Tsinghua
University in Beijing, where he is now Dean of the Institute
for Interdisciplinary Information Sciences.
Prof Yao’s research interests are in the theory of computation and its applications to cryptography, algorithmic
economics, and quantum computing. He is recipient of
the prestigious Turing Award in 2000, as well as numerous
other honors and awards, including the George Polya Prize,
the Donald E. Knuth Prize, and six honorary doctorates.
He is a member of the US National Academy of Sciences,
the American Academy of Arts and Sciences, the Chinese
Academy of Sciences, Academia Sinica, and the Academy
of Sciences of Hong Kong.
Distinguished speakers including Nobel Prize winners,
corporate leaders, entrepreneurs and key financial policy
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Asia Pacific Physics Newsletter
Prof Andrew Yao talks about “Quantum Computing: A Great Science in
the Making” at HKUST 25th Anniversary Distinguished Speakers Series.
shapers were invited to speak at the HKUST 25th Anniversary Distinguished Speakers Series. Prof Steven Chu, Nobel
Laureate in Physics in 1997 and former US Secretary of
Energy, was invited as the inaugural speaker of the series.
Other speakers include Mr Jean-Pascal Tricoire, Chairman
and Chief Executive Officer of Schneider Electric; Mr Wang
Shi, Founder and Chairman of China Vanke; Prof Dan
Shechtman, Nobel Laureate in Chemistry in 2011; Prof
Zhong Lin Wang, Hightower Chair in Materials Science and
Engineering and Regents’ Professor at Georgia Institute of
Technology; Dr Raghuram G Rajan, Governor of the Reserve
Bank of India; Mr Pinky Lai, Founder and Design Director
of Brainchild Design Group and Brainchild Design Consultants; and Dr Qi Lu, Executive Vice President of Microsoft’s
Applications and Services Group. More talks are also being
lined up.
Reproduced with permission from The Hong Kong University of
Science and Technology.
NEWS
Physics from Iran’s Point of View
Zahra Gh.Moghaddam
QShahid Beheshti University (National University of Iran)
F
rom the time of Ibn-e-Heytham the spectacular
Iranian physicist in 965 A. D to the time when the
Physics Society of Iran was founded in 1932, with
the guidance of Dr Hesabi, the borders of Iranian physics'
community have become greater and broader. Although
PSI's activities were quite limited and often interrupted and
gradually faded at the time, it was gathering and holding
sessions called “The Group of Physics and Chemistry” which
was the inauguration of physics research studies in Iran.
Nowadays, the physics curricula at the major Iranian
research institutions are comparable to those of any
American or European universities and, unlike in earlier
generations, the majority of courses are taught by physicists
educated in Iran. Women also found their way through
fundamental science studies as well as other majors and they
are now active as professors and researchers throughout Iran.
The frontier of physics in Iran concerns research studies
in which many important branches in physics, such as
Atomic, Molecular, and Optical Physics; Condensed Matter
and Materials Physics; Nuclear Physics; Particles Physics and
Fields, Cosmology and Early Universe, and Astrophysics;
Statistical and Nonlinear Physics, Plasma Physics, and Fluid
Dynamics; Soft Matter, Biological, and Interdisciplinary
Physics are covered. There are numbers of institutions
and universities in Iran working on physics in various
topics from theory to experiment. Outstanding centers in
fundamental studies through which young researchers can
benefit the atmosphere to thrive in various fields, provide
weekly seminars, courses and schools on recent significant
advances in physics. They also have, invited speakers from
overseas to keep up with the world's updated topics. Signing
the Memorandum of Understanding with overseas groups
like Diamond Light Source, is another big stride for Iran
toward joining the international collaborations. From Iran's
contribution to several international projects, SEASEM and
DIAMOND Light source, and collaboration with the CMS
projects at LHC, can be indicated.
Numbers of Iranian outstanding physicists in 1932.
Iran's (physics department of Shahid Beheshti University) PhD exchange
program not only in physics but in various fields of research.
May 2016, Volume 5 No 2
49
NEWS
The first pair of steel tables and shielding superstructures for LHC, CMS
experiment which has been manufactured in Iran, Arak, an industrial
town 200 km west of Tehran.
Shahid Beheshti University (National University of Iran)
Fordow Nuclear facilities, Near Qom, Iran.
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Asia Pacific Physics Newsletter
Physics branches in Iran are keeping up with global
updates, for instance, from the recent works in High energy
physics, studies on string theory, extra dimension and
holographic description of gravity, AdS/CFT correspondence
and its variants, string cosmology, dS holography, tachyon
physics, are prominently popular. Moreover, High energy
phenomenology is also an area of interest; studies on new
physics beyond Standard Model like MSSM, CP violating
phases, Neutrino physics and Dark Matter are quite notable.
Likewise, in Astrophysics and Cosmology sector, studies
on Early Universe and matter anti-matter asymmetry are
highlighted as well.
In order to motivate PhD students and enrich the physics
research studies, Iran initiated the Annual Prize bestowed
in a number of categories in physics for the best written
PhD thesis.
After the nuclear agreement between Iran and 5+1 countries, the prospect of Iran's physics research projects is getting
to be more promising. Consequently, Iran can be expected to
be even more involved in international collaborations such as
ITER, the massive nuclear fusion project, and more experiments at CERN. For example, since the great discoveries in
neutrino physics have been made in mines and tunnels to
shield the experiments from cosmic rays, the Fordow facility,
one of the peacefully privileged nuclear facilities which has
been built under a mountain near the city of Qom, could be
used for a variety of possible physics experiments, including
a neutrino detector or a linear accelerator.
Additionally, a few major scientific facilities are currently
under preparation within Iran, including the Iranian
National Observatory, a 3.4-meter telescope planned to
perch atop Mount Gargash in central Iran, and the Iranian
Light Source Facility in collaboration with SESAME and
DIAMOND light source, under construction near Qazvin.
These could see more international collaboration under the
deal as well.
In order to keep up with the technology advancements in
practical zone in Iran, both engineers and physicist establish
science based companies working on manufacturing and
designing the extensive range of physics' laboratory equipment including general to advanced experiments.
All in all, bearing the bright talents and hardworking
members, Iran's imminent future in physics is quite auspicious. Furthermore, by being more associated with international collaborations, Iranians could attend international
schools, conferences and visits much easier than before.
NEWS
9th Yukawa-Kimura Prize awarded to
Associate Professors Nishimura and
Hanada
O
n 20 January, an award ceremony for the 9th
Yukawa-Kimura Prize of the Yukawa Memorial
Foundation took place in the Panasonic Auditorium of the Yukawa Hall, Yukawa Institute for Theoretical
Physics (YITP).
The award recipients -- Associate Professor Jun Nishimura
of the Institute of Particle and Nuclear Studies, High Energy
Accelerator Research Organization (KEK), and ProgramSpecific Associate Professor Masanori Hanada of the Hakubi
Center for Advanced Research and YITP -- were each
presented with a certificate, medal, and cash prize from
Director Taichi Kugo of the Yukawa Foundation. Professor
Nishimura delivered a commemorative lecture, titled
"Numerical simulation of supersymmetric gauge theory and
gauge/gravity duality", on behalf of the awardees.
The Yukawa-Kimura Prize was established in 2007 by the
Yukawa Memorial Foundation (a public-interest corporation
since 1 April 2012) based on a donation from Ms Hiroko
Kimura, widow of Professor Toshiei Kimura of Hiroshima
University's Research Institute for Theoretical Physics
(RITP), which was merged into YITP in June 1990. The Y-K
Prize honors outstanding achievements in areas related to
fundamental theoretical physics, including gravitational
physics, spatiotemporal theory, and field theory. Recipients
are chosen by a YITP selection committee.
Reproduced with permission from Kyoto University.
From left: YITP Director Misao Sasaki, Yukawa Foundation Director Kugo, Associate Professor Nishimura, Program-Specific Associate Professor Hanada,
and Dr Shinya Aoki, chair of the Yukawa-Kimura Prize selection committee
May 2016, Volume 5 No 2
51
NEWS
Report on IPS Award 2015
Phil Chan
IPS Awards Chair 2016
IAS Associate Fellow
About the IPS Awards 2015
The Institute of Physics, Singapore (IPS) presents awards
annually to recognise and reward local or international
physicists for outstanding achievements in their respective
fields made in Singapore.
It is IPS’ objective to identify and honour physicists
who are currently doing state-of-the-art physics research
or making innovative physics education contributions on
an annual basis.
These awards serve to encourage younger members of the
Singaporean physics community to attain greater success in
future as they probe the marvelous yet unknown frontiers
of the physical Universe and communicate physics to the
schools and public.
In celebration of SG50, IPS presented awards to more
than one awardee in some of the categories when there are
other deserving outstanding candidates. This year’s award
ceremony was held in conjunction with the Conference on
New Physics at the Large Hadron Collider Banquet organised
by Institute of Advanced Studies, Nanyang Technological
University at Chui Huay Lim Club on 3rd March 2016. The
2015 SG50 outstanding IPS Medalists are given below.
Prof Lai Choy Heng receiving the President’s Award from IPS President Prof Sow Chorng Haur
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Asia Pacific Physics Newsletter
NEWS
Prof Alfred Huan receiving the President’s Award from IPS President Prof Sow Chorng Haur
IPS Crescendas Award for Outstanding Secondary
School Physics Teacher
Mr Tan Chong Chay (Hong Kah Secondary School)
IPS Crescendas Award for Outstanding Junior College
Physics Teacher
Mr Sze Guan Kheng (Raffles Institution)
IPS Crescendas Award for Outstanding Polytechnic
Physics Lecturer
Dr Randall Cha (Temasek Polytechnic, School of
Engineering)
Mr Jeremy Chong (Nanyang Polytechnic, School of
Engineering)
IPS Crescendas Award for Outstanding ITE Physics
Lecturer
Mr Tay Khee Wee (Institute of Technical Education,
College West)
IPS Cadi Scientific Award (Group) for Public Awareness of Physics
Mr Soh Kim Mun, Mr Ang Poon Seng, Mr Albert Ho,
Mr Albert Lim (The Astronomy Society of Singapore)
IPS Cadi Scientific (Individual) Award for Public
Awareness of Physics
Mr Remus Chua (Navagis Asia Pacific Pte Ltd)
IPS Nanotechnology Award
Assoc Prof Xiong Qihua (Nanyang Technological
University)
Assoc Prof Fan Hongjin (Nanyang Technological
University)
IPS World Scientific Award
Asst Prof Zhang Baile (Nanyang Technological University)
Special Institute of Physics, Singapore Award
Adj Assoc Prof James Lee (National University of
Singapore and National Cancer Center)
Institute of Physics, Singapore President’s Award
Prof Alfred Huan (Nanyang Technological University)
Prof Lai Choy Heng (National University of Singapore)
Distinguished Institute of Physics, Singapore Honorary
Fellowship Award
Prof Chang Ngee Pong (City College of The University
of New York)
May 2016, Volume 5 No 2
53
NEWS
Joint IAS-ICTP School on
Quantum Information Processing
Raymond Ooi
Quantum & Laser Science (HIR Building), Department of Physics,
University of Malaya
T
he Institute of Advanced Studies (IAS) at the Nanyang
Technological University (NTU) and the Abdus
Salam International Centre for Theoretical Physics
(ICTP) jointly organised a School on Modern Topics in
Quantum Information Processing in Singapore. It was
held from 18 January to 29 January 2016 at the Nanyang
Executive Centre, NTU. The two-week event was filled with
quantum information talks and public lectures by 3 physics
Nobel laureates on three separate occasions, namely Prof Sir
Anthony Leggett (Physics 2003), Prof Serge Haroche (Physics
2012) and Prof Gerard `t Hooft (Physics 1999).
A total of 85 international participants from various
developing countries such as Thailand, Malaysia, India and
China, as well as from Australia, Korea and United Kingdom.
The topics covered in the first week revolved around quantum
algorithm and quantum computers, topological quantum
computation, Majorana fermions. In the second week,
the main topics were experimental aspects of quantum
computation and quantum information, fundamentals
concepts like entanglement, matrix product states, tensor
network and quantum correlations, quantum metrology
and interferometry.
The first day, 18 January 2016 (Monday), kicked off
with five talks on quantum information after the opening
ceremony in the morning by Prof KK Phua, Director of IAS
who spoke the close collaboration between ICTP and IAS.
K.K. Phua also mentioned about the immense contribution
of Adbus Salaam in setting up the ICTP. On the second
day, the program stretched all the way till the evening with
a public talk (6:00pm to 8:00pm) by three Nobel laureates
from three different fields; Prof Carlo Rubbia (Physics 1984),
Prof Arieh Warshel (Chemistry 2013) and Prof John Robin
Warren (Physiology or Medicine 2005). The central theme of
the forum was Science, Scientists and Society and the event
was held at the School of Art, Design and Media’s Auditorium
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Asia Pacific Physics Newsletter
at NTU. The event was fully packed and was chaired by
Prof Bertil Andersson, NTU President, who optimized the
time to encourage intelligent questions from the audiences,
particularly students.
On the third day, a morning lecture was given by Sir
Anthony Leggett on the prospects of topological quantum
computing using physical effects in condensed matter. He
showed mathematically how non-Abelian systems can be
topologically protected, and he discussed at length the
fractional Quantum Hall effect (FQHE) in torus geometry
and elaborated on the Kitaev model for spin half system
in honeycomb lattice. He also touched on p-wave Fermi
superfluid of Helium-3 in two dimensional geometry with
pairing in spin triplet. Finally, he highlighted the issues and
limitations of the optical lattice systems for use in quantum
information technology as compared to superconducting
qubits.
In the afternoon of the fourth day, Serge Haroche
talked about quantum metrology with nonclasical atomic
Rydberg states. He showed how one could achieve precision
measurement below the standard Quantum Limit (SQL)
and approach the Heisenberg limit (HL) by entangling the
Dicke states in the angular momentum of Rydberg atom with
linear Stark effect. The precision technique involves the use
of the Schrodinger’s cat state (SCS), the Ramsey technique
and dynamical quantum Zeno effect.
On the fifth day, Gerard ‘t Hooft talked about cellular
automaton. He introduced a novel idea of quantum cells that
contain quantum information of all interrelated events from
the past. The insight of the idea may stem from the 3-point
correlation function. He also alluded to the connection with
conformal symmetry. According to him, quantum field
theory contains all quantum correlations that arise naturally.
Prof Gerard ‘t Hooft also delivered a second public talk
in the evening at NUS (Lim Seng Tjoe LT) concerning the
NEWS
roadmap and exploration toward colonization of planet Mars
involving some high-tech projects. He also mentioned the
issues like cost of such a plan and the funding for advanced
robotic and information technologies, the feasibility of using
transit vehicle to land on Mars, and the possibility of survival
on Mars as a “Living Unit” including the problems of weight,
foods and water supply.
Synopsis of lectures at the School
For the School, the lecture series on quantum information
were given by several experts in the fields of quantum
information.
Matthias Troyer talked about the computation and
numerical aspects of quantum algorithms. According to him,
the performance of quantum computers demonstrated by D
wave is not exponential as expected in theory nor is there any
quantum speedup, even though Google is moving towards
quantum computing with ambitious “save the world” aspirations. There is a lot can be learned from there. He discussed
the potential weaknesses and possibilities of improvement
in connection with quantum Monte Carlo simulation and
quantum annealing involving Ising spin glass. The necessary
ingredient not only quantum algorithm but also quantum
software engineering or programming language.
David DiVincenzo showed that superconducting qubit
is promising for quantum computer due to its high fidelity.
He also discussed the double well system in 2DEG with one
single and three triplet states, which somewhat reminds us
of the four states of 1s2s in atomic helium. It is interesting to
learn that it is also possible to lift quantum degeneracy via
introduction of defects & electron tunneling.
Ady Stern talked about the topological state of matter and
Majorana fermions. The lecture covers multifold degeneracy
from fractional quantum Hall to topological quantum
computation. He gave a good introduction on the quantum
Hall effect and discussed the emergence of fractional spins.
defined the topological sector, the edge state as 1D system
with anomaly and disordered quantum Hall state.
According to Jiannis Pachos, the concept behind topology
is related to the concept used in string theory, particularly
through the Chern-Simons theorem. We learnt that the
Majorana fermions and anyon can be described by the
quantum phase and the Dirac equation. He discussed the
D wave 512 qubits quantum computer (courtecy of D-wave Systems Inc.)
May 2016, Volume 5 No 2
55
NEWS
Original sample of FQHE
Toric code - spin 1/2 on square lattice is Abelian from Pauli
algebra, has topological entanglement entropy that is useful
for topological quantum memory. It is learnt that conversion
from one ground state into another ground states can be
achieved via transformation and all topological models are
error correcting codes.
The talks by Stern and Pachos have also touched on
Forster theorem cavity, Bogoliubov de Gennes, Majorana
Fermion for universal quantum computation arising from
Dirac fermions, Ising model, Bose Hubbard, Mott insulator,
superfluid, BCS regimes, braiding concept in topology,
anyons, Chern-Simons theory, Abelian and non Abelian
systems.
Andreas Winter presented the concept of entanglement
using the entropic approach especially the Shannon entropy
with connection with classical communication channels, and
made use of the bounds of inequality relations.
Jeremie Roland talked about the recipes in quantum
computations, namely the necessary algorithms that
involves the Oracle problem and Deutsch algorithm in
terms of circuits, the concept of reversible computation and
universal quantum gates, complexity issue and the power
and capabilities of quantum computers. He discussed the
thermodynamics aspect of quantum information in terms
of quantum gates.
The lecture given by Xin Wan touched on the materials,
devices and algorithms used for the development of a
FQHE (Fractional Quantum Hall effect)-based topological
quantum computer. He showed how fractional quantum Hall
effects can be observed in two-dimensional electron system
such as GaAs quantum wells or in high mobility graphene.
Besides, he presented the Laughlin states that support gapped
Abelian quasiparticle excitations which carry a fraction of
an electron charge. Gapless chiral edge excitations are also
described by Laughlin states in which the quasiparticles
propagate along the edge. He also introduced the model of
anyons (theory of a two-dimensional medium with a mass
gap, where the particles carry locally conserved charges) as
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Asia Pacific Physics Newsletter
well as the Moore-Read state. In his lectures, he also showed
how interferometric experiments can be demonstrated and
how we harness current technology to create anyons and
also how we can manipulate them to achieve braiding. The
final session was about the algorithms to compile topological
quantum gates. He ended the lecture with an interesting
remark that the Chinese characters may contain some
topological information.
Vadim N. Smelyanskiy elaborated on the theory of rf
SQUID as superconducting qubit and the detailed physics of
flux associated with the magnetic fields and the underlying
tunneling, diffusion and noise phenomena. He presented
the experimental implementation of quantum computation,
particularly on quantum annealing with flux qubits. He first
presented the Hamiltonian associated with the flux qubit in
rf-SQUID (superconducting quantum interference device)
and the coupling between the qubits. He then introduced the
origin of the flux noise as the fluctuations of magnetization
formed by the impurity magnetic moments in the oxide layer
on the surface of superconductor and expressed the noise
as a contribution to the total Hamiltonian. From the spindiffusion equation obtained using the Langevin approach,
the spin diffusion noise power spectrum was calculated. The
effect of geometry on the spin diffusion noise spectrum was
analysed for rectangular, cylindrical and elliptic-cylindrical
wire. In the analysis of the noise he presented many other
interesting analytical approaches such as diffusion eigenvalue
problem in elliptic coordinates, graphical solution of the
eigenvalue problem, Mathieu harmonics, dependence of
the noise spectrum on Aspect Ratio, inhomogeneous spin
diffusion equation, sum rule for magnetic susceptibility.
The lecture by Frank Verstraete covered the topics of
entanglement, matrix product states and tensor networks. He
first introduced a concept called the monogamy of entanglement and then the translational invariance, area law and local
singlets as the criteria to minimize the energy of the systems.
AKLT model was used to study matrix product states wavefunction which fulfill the previously mentioned criteria. He
then presented the fundamental theorem of multipartite
state, and related it to Cauchy-Schwarz inequality. Finally, he
introduced and analyzed RVB states which have applications
in topological quantum computation.
The presentation by Rainer Dumke was on the advances
in quantum information technology with cold and trapped
neutral atoms in magnetic trap. He presented the utilization
of neutral atoms in clocks, interferometers, magnetometers,
atomtronics, many-body physics, etc. Then, he mentioned
the Divincenzo criteria which includes the five criteria that
any candidate quantum computer implementation must
NEWS
Speakers and participants of the Joint IAS-ICTP School on Quantum Information Processing.
satisfy and another additional two criteria for quantum
communication. He showed that it is possible to realize
qubits using neutral atoms and presented the traps for neutral
atoms as well as the gates and architectures with similar
system. According to Rainer, qubits can be encoded in the
vibrational states of atoms in tight traps. He also showed
mathematically and schematically how the atoms are being
trapped using magnetic fields and the problems that may
arise during the experimental realization. Experimental data
from relevant literature was also shown.
Vlatko Vedral's lecture was about quantum correlations.
He first gave an introduction to entanglement as defined by
Schrodinger using the "Mean King Problem" as a case study.
He touched on the LOCC (local operations and classical
communications) which is a method in quantum information theory the result of a local operation performed on part
of the system is "communicated classically to another part on
which another local operation is also performed. He emphasized that LOCC cannot increase entanglement and that if
local unitary is done on two parties, then the entanglement
should remain constant. He also showed mathematically that
the entanglement of a separable state is zero. The final part
of his lecture was about majorization and the higher forms
of correlations (discord and coherence) which brought us to
the topic of quantum macroscopicity.
Tomasz Paterek introduced the laws of quantum communication which encompass information gain, information
causality and entanglement gain. Using concepts in quantum
information theory such as symmetry of conditional mutual
information, positivity of mutual information and data
processing inequality, Tomasz mathematically proved an
indisputable law of communication, that is, information gain
is bounded by the communicated information. In layman
terms this means that the amount of information received
in a communication cannot exceed the amount of information being transmitted. The 2nd law, which is Information
Causality states that information that a receiver can gain
about a previously unknown set of data from his sender, by
using all of his local resources (which may be correlated by
the sender's resources) and m classical bits from the sender,
cannot be greater than m. Information Causality excludes
no-signalling (information cannot be transmitted faster than
light) correlations which give access to too much remote data.
Tomasz ended the session with the 3rd law which states that
the increase of relative entropy of entanglement between two
remote parties is bounded by the amount of non-classical
correlations of the carrier with the parties as quantified by
the relative entropy of discord.
The school ended with the lecture given by Lau Shau-Yu.
He presented something completely different yet exciting
which is the utilization of techniques in quantum optics,
atom optics and laser cooling and trapping for precision
measurement of various fundamental constants in classical
physics such as Newton's gravitational constant G. He
showed photos and schematic diagrams of how the experiment was done in other research groups and what his group
is currently working on. According to Shau-Yu, the precision
measurement method he studies is currently the most precise
and accurate measurement of G ever present.
May 2016, Volume 5 No 2
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NEWS
Event Highlights from HKUST Jockey
Club Institute for Advanced Study
Vision to Future Colliders
IAS Program on High Energy Physics
4 – 29 Jan 2016
Building on the success of the same program in 2015, IAS
co-organized again with the Institute of High Energy Physics
(IHEP) of the Chinese Academy of Sciences for a one-month
program on High Energy Physics, which attracted more than
100 participants for fruitful academic exchanges.
Apart from attendees of 2015, the program in 2016
welcomed a number of new faces from institutions in
the US, Europe, Russia, Japan, Korea, mainland China,
Taiwan and Hong Kong. Upon completion of 15 talks and
discussion sessions in the program as well as 60 talks and a
forum session in the conference, participants were invited to
contribute white papers to the particle physics community by
documenting the physics goals, options of future colliders,
and the reach of the related experiments. Similar to the
program in 2015, papers submitted in 2016 are expected to
be published by World Scientific in dedicated issues of the
International Journal of Modern Physics A.
Experts in high energy physics came to HKUST from around the world and exchanged ideas in a panel discussion session.
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Asia Pacific Physics Newsletter
NEWS
Ways to Manipulate Waves
IAS Winter School and Workshop on Advanced Concepts in
Wave Physics: Topology and Parity-time Symmetries
11 – 15 Jan 2016
To explore the application of modern concepts such as
topological invariants and parity-time symmetry to the
manipulation of wave, IAS organized a winter school and
workshop on Advanced Concepts in Wave Physics: Topology
and Parity-time Symmetries.
In additional to the 10 lectures covering topological
concepts, parity-time symmetry notions and their applications to physics of waves given by renowned physicists, over
30 talks were delivered by the speakers. Young scientists also
seized the occasion to share their research with program
participants through poster display and presentations. The
ample discussions among participants during the program
not only facilitated the exchange of research ideas, but also
promoted more research collaborations across institutions.
Participants shared their research ideas and findings during the poster
display and presentation session.
When Condensed Matter Meets Cold Atom
IAS Program and Croucher Conference on Topological
Phases in Condensed Matter and Cold Atomic Systems
11 – 19 Dec 2015
The search for topological phases and the study of their
properties have become two of the most important topics
in condensed matter physics and cold atomic gases in recent
years. The IAS Program and Croucher Conference on
Topological Phases in Condensed Matter and Cold Atomic
Systems held last Fall provided a platform for physicists and
researchers from both fields to get together to share their
research insights and experiences.
Around 140 participants joined the 9-day event and over
60 talks were delivered. Recent developments in topological
insulators, topological crystalline insulators, Majorana
fermions and nodal topological phases such as 3D Dirac
and Weyl semimetals were covered in the Condensed Matter
session while artificial magnetic field, spin-orbit coupling,
novel optical lattices and quantum fluids were discussed in
the Cold Atom session.
Conferees enjoyed the conversation with Prof Patrick A. Lee (right), IAS
Visiting Professor and organizing committee member of the conference.
Reproduced with permission from HKUST Jockey Club Institute for
Advanced Study.
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Highlights from the Asia Pacific Region
Holographic Topological Insulator
Topological Insulators are novel materials that possess robust
conducting surfaces or edges despite being bulk insulators.
Conceptually, they are interesting because their surface or
edge states are protected by the topological properties of their
bulk bandstructure. From a technological standpoint, they
are also exciting due to their potential as dissipationless wire
Fig. 1.
(Color Online) A simplest illustration of the exact holographic
mapping [3]. The original system consists of the 23 = 8 sites in the top
row. An unitary transform acts on the Hilbert spaces on each pair of these
sites and separates them into high energy (UV, red) and low energy (IR,
blue) degrees of freedom. The high energy degrees of freedom forms the
first (n = 1) layer of the dual system, while the low energy degrees of
freedom form the input to the next iteration of unitary transformation.
This is repeated until there is no more pair to be iterated. The result is a
rearrangement of the original system into a dual system with layers of
different energy scales arranged in a pyramid-like fashion.
interconnects in nanoscale circuits and spintronics devices
[1]. So far, the three types of topological insulators that have
been experimentally realized are the 2D quantum spin Hall
(QSH), 2D quantum anomalous Hall (QAH) and the 3D
time-reversal invariant Z2 topological insulator, for instance,
in HgTe quantum wells, Cr-doped BiSeTe thin films and BiSb.
Parallel to these advances in topological insulators is
the intense interest of holographic duality in the theoretical
physics community. First proposed by Witten, Maldacena,
Klebanov and others in 1998, it is also known as the
Anti-de-Sitter space/Conformal Field Theory (AdS/CFT)
correspondence. Its principal idea is that a quantum field
on a fixed background geometry can be regarded as a
"hologram" containing the same information as a "dual"
gravitational system one dimension higher. As the extra
emergent dimension in the dual system has the physical
interpretation of scale, holographic duality enables the
scaling behavior of the original system to be understood in
terms of spatial dynamics in the dual spacetime. The best
understood example of holographic duality is the correspondence between 4-dimensional super-Yang-Mills theory
and 5-dimensional supergravity, where the strongly-coupled
limit of the super-Yang-Mills theory corresponds to the classical (weakly-coupled) limit of the dual gravitational theory.
In a similar flavor, holographic duality has also been fervently
employed in the study of strongly-coupled condensed matter
systems like quantum critical heavy Fermion systems and
putative high-temperature superconductors. Indeed, by
Fig. 2.
Left) A sketch of a topological insulator region in the 3D holographic dual corresponding to a 2D quantum anomalous Hall system with
a very small gap. Right) Plot of the gap of onsite correlator in the presence of an entanglement cut at the nth layer. The background color density
represents the Chern number density, with the two distinct left and right peaks at the scales of lattice regularization and Dirac cone gap respectively.
Evidently, the correlator is gapless only if the cut is made between the two peaks, where the Z2 index is purportedly nontrivial.
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Asia Pacific Physics Newsletter
RESEARCH HIGHLIGHTS
providing an alternative route to understanding the elusive
behavior of strongly-coupled systems, holographic duality
is a quintessential example of the symbiosis between high
energy physics and condensed matter physics.
Presented with illustrious developments in these two
directions, it is natural to ask what holography can teach us
about topology. A rst step was made in [2], where a systematic
holographic decomposition of a lattice system was developed.
This approach, known as the exact holographic mapping
(EHM), allows one to write down the holographic dual of
any given lattice system through repeated applications of
unitary mappings (see Fig. 1). This dual possesses a Hilbert
space identical to that of the original system, but is arranged
in layers representing different energy scales.
In the spirit of holography in high energy physics, one
can define the classical geometry of the dual system by
identifying the geodesic distance between two points on it
with the upper bound of their corresponding correlation
functions. As detailed in [2] and [3], this upper bound is
given by the mutual information between the corresponding
causal cones of the two points in the original system. One
finds the duals of a critical zero temperature and nonzero
temperature fermionic system being Anti-de-Sitter (AdS)
space and the Bañados, Teitelboim and Zanelli (BTZ) black
hole respectively, in agreement with expectations from other
approaches in AdS-CFT.
Very interestingly, the exact holographic mapping (EHM)
also provides another way of understanding the relationship
between different types of topological insulators. Specifically,
applying the EHM onto an almost gapless 2D quantum
anomalous Hall (Chern) insulator results in a dual system
containing a 3D time-reversal breaking Z2 topological insulator region (Fig. 2). This can be understood as follows. A 2D
Chern insulator is characterized by one or more Dirac cones
in momentum space, while a 3D Z2 topological insulator
has an odd number of Dirac cones on its spatial surfaces.
Each lattice Dirac cone carries a topological flux (Chern
number) of one, with half residing near its singularity and
the other half arising from lattice regularization. If a Dirac
cone is almost gapless, the scale of the singularity will be
much smaller than that of lattice regularization. In this case,
the EHM separates these two contributions into two distinct
Dirac cone regions in the emergent scale direction of the
dual system. The region between these Dirac cones can be
identified with a bona-de Z2 topological insulator, as justified
in [4] by comparing entanglement spectra. At a deeper level,
this reveals the helical surface states of the 3D topological
insulator as direct manifestations of the parity anomaly of
2+1-D Dirac cones. Mathematically, one identifies the Berry
curvature density distribution in the dual system with the
gradient of the θ-angle of the effective Axion topological
field theory.
Indeed, the application of the EHM on topological insulators has gone beyond traditional studies restricted to the
correspondence between critical theories and AdS spacetime.
It forges a suggestive relationship between the two bulk-edge
correspondences that has created much excitement in the
physics community: Holographic Duality which relates a
conformal field theory on the edge with a gravitational theory
in the bulk, and Topological bulk-edge correspondence
which relates a conformal field theory on the edge with a
nontrivial topological invariant from the bulk states.
[1] X. Zhang and S.-C. Zhang, SPIE Defense, Security, and Sensing,
837309 (2012).
[2] X.-L. Qi, arXiv preprint arXiv:1309.6282 (2013). [3] C. H. Lee and X.-L. Qi, Physical Review B 93, 035112 (2016). [4] Y. Gu, C. H. Lee, X. Qi, and et. al., to be submitted..
Dr Ching-Hua Lee
Astar and Stanford University
Daya Bay Reactor Neutrino Experiment
Daya Bay Reactor Neutrino Experiment (hereinafter referred
to as “Daya Bay Experiment”) is based in Guangdong
Province, China. Its main objective is to look for a new kind
of neutrino oscillation and precisely measure its oscillation
amplitude – denoted by the parameter sin22θ13 – using
electron antineutrinos generated from nuclear reactors.
The experiment built a 3 km tunnel and 3 underground
experimental halls very close to reactors, from 400m to
1600m. In each experimental hall, there is a water pool in
which, two to four neutrino detector modules are installed,
as shown in Fig.1. The civil construction of the experiment started in October 2007, and data taking started on
December 24, 2011.
On March 8, 2012, the Daya Bay Collaboration announced
that a new kind of neutrino oscillation (corresponding to
neutrino mixing angle θ13) is discovered. Its measured oscillation amplitude is 9.2%, with an error of 1.7%. The statistics
significance of this observation is 5.2 standard deviation,
corresponding to a probability of one part per ten million
for null oscillation (Phys. Rev. Lett. 108, 171803(2012)). This
result revealed a basic property of neutrinos and opened
a gateway towards the understanding of the “mystery of
matter-antimatter asymmetry”. It was selected into the top
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RESEARCH HIGHLIGHTS
local significance is greater than 4 standard deviations. This
result provided new evidence to the study of the so-called
Reactor Antineutrino Anomaly, and to the improvement of
the reactor antineutrino model (Phys. Rev. Lett. 116, 061801
(2016)).
Daya Bay experiment will continue its data taking until
2020, to improve the accuracy of sin22θ13 which is very
important to neutrino physics, astrophysics, cosmology and
other frontier of sciences.
Fig. 1.
Top view of the experiment hall: 4 neutrino detectors are in a
water Cherenkov detector pool, with RPC detectors visible at the far end.
Lei Liu
Institute of High Energy Physics, Chinese Academy of
Sciences
Exploring the Universe in a New Light
Fig. 2.
Regions allowed at the 68.3%, 95.5% and 99.7% confidence
levels by the Daya Bay experiment. The best estimate were sin22θ13 =
0.084±0.005 and |Δm2ee| = (2.42±0.11)×10-3 eV2(black point)
ten scientific breakthroughs of the year 2012 by the U.S.
"Science" magazine.
In 2013, Daya Bay reported the first direct measurement
of the electron antineutrino mass-squared difference (Δm2ee).
This result is consistent with Δm2μμ measured by muon
neutrino disappearance, and will improve our understanding
of the subtle details of neutrino oscillations (Phys. Rev. Lett.
112, 061801 (2014)).
In 2014, based on 217 days of day taken with 6 detectors,
combined with 404 days of data taken with all 8 detectors,
Daya Bay improved the precision of θ13 and Δm2ee by almost
a factor of two, reaching 6% and 5%, respectively (Phys. Rev.
Lett. 115, 111802 (2015), Fig.2). A search for light sterile
neutrino mixing was performed and a new limit is given.
Another independent analysis using neutrons captured on
hydrogen also obtained θ13 measurement with a statistical
significance of 4.6 standard deviations (Phys. Rev. Lett.113,
141802 (2014)).
In 2015, Daya Bay reported its first measurement of the
reactor antineutrino spectrum, and observed an excess of
neutrinos around 6MeV compared to the prediction. The
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Asia Pacific Physics Newsletter
This historic press release for the event named GW150914
from the LIGO Scientific Collaboration marks a turning
point in the history of astronomy:
“The gravitational waves were detected on September
14, 2015 at 5:51 a.m. Eastern Daylight Time (09:51 UTC)
by both of the twin Laser Interferometer Gravitationalwave Observatory (LIGO) detectors, located in Livingston,
Louisiana, and Hanford, Washington, USA.”
The new era of gravitational wave astronomy that begins
with the LIGO detection will enable us to see the universe,
literally, in a new light.
Our Understanding of Gravity
Newton formulated the inverse square law of gravitation. It
had the mysterious feature that if the source of gravity were
to move, its effect would be felt instantaneously on objects
even when they are separated by celestial distances. We now
understand that this is only approximately true when the
motions are slow compared to the speed of light which is true
in the solar system and hence the success of Newton’s law.
Einstein’s special theory of relativity posited that the finite
speed of light (i.e. of electromagnetic waves) is the same for
all observers in constant relative motion and limits the speed
at which physical influences can be transmitted. Noting that
this conflicted with Newton’s instantaneous law, Einstein
embarked on a heroic quest for the relativistic laws of gravity.
This culminated in the General Theory of Relativity
(GTR) whose complete equations were presented to the
Prussian Academy in Berlin on 25th November 1915, now
more than 100 years ago. GTR was revolutionary because it
RESEARCH HIGHLIGHTS
changed our conception of space and time. In General Relativity space-time is no longer the passive stage for physical
events that it was for Newton - they are equal actors in the
drama of physical events. Einstein’s equations tell you that
matter (or energy in general) stresses and curves space-time
as if it were an elastic medium. In this framework, the sun
curves the space-time around it and the earth responds to
that curvature and moves in the straightest possible path in
this curved geometry. The orbits are now corrected from the
perfect ellipses of Newton though, in the solar system, this
is significant only for Mercury. Einstein moreover predicted
that light, having energy, would also be subject to bending
and this has indeed been measured, most dramatically in the
gravitational lensing by massive galaxies. Einstein’s equations
also form a framework for cosmology and give a quantitative
understanding of the evolution and large-scale structure of
the universe.
Black Holes and Gravitational Waves
One of the most remarkable predictions of Einstein’s theory,
for which there is no Newtonian analogue, are black holes.
Schwarzschild found the first such exact solution shortly after
Einstein’s paper though its interpretation as a non-rotating
black hole came much later. The Kerr solution describing
the rotating case was found only about half a century later.
The astrophysical significance of these solutions gradually
emerged from the work of Oppenheimer and Snyder as
well as S. Chandrasekhar’s work on neutron stars, which
established the upper Chandrasekhar limit. It suggested that
black holes might be the end point of stellar collapse. There
is now astrophysical evidence for black holes, which range
from a few solar masses to several million solar masses (at
the centre of galaxies). Theoretically, what is remarkable
about black holes are that they are pure curved geometries
with no matter, yet carrying energy and angular momentum.
In 1916 Einstein himself predicted gravitational waves as
solutions of the linearized version of his). These are small
distortions of the ‘elastic medium’ of space-time that travel
at the speed of light and are set off by the motion of massive
objects in space-time. A good analogy is ripples of water
waves set off by a pebble thrown into a still pond, except
that space-time is very stiff (since Newton’s gravitational
constant is small) and it needs large masses and violent
motions to bend it and set off measurable gravitational waves.
Technically, it is the second time derivative of the quadrupole
moment of a matter system that leads to gravitational radiation. Contrast this with electromagnetic radiation which is
determined by the first time derivative of the dipole moment
of a charge distribution.
Both of these novel predictions of GTR entered into
the LIGO detection of September 14, 2015. Based on the
observed signal and the theoretical framework that interprets
it, what LIGO observed, were exactly these gravitational
waves set off by the merger of a system of binary black
holes. Two mutually orbiting black holes of 29 and 36 solar
masses were deduced to have merged into a spinning black
hole of about 62 solar masses and spin about two-third of its
maximal possible value. Thus, about 3 times the mass of the
sun was radiated (according to Einstein’s formula m=E/c^2)
as gravitational waves in a fraction of a second with a peak
power output 50 times that of the whole visible universe! This
merger was an enormous gravitational dynamo.
Unfortunately, from just two measurements at Hanford
and Livingston, the exact location and time of the event have
been hard to pinpoint. It happened roughly 1.3 billion years
ago and has only been localised to a broad swathe of the sky
in the southern hemisphere.
It was extremely fortunate that the merger of a black hole
binary sourced the first detection of gravitational waves. This
means that the spiraling into a merger is fully described by
Einstein’s equations of general relativity, uncontaminated
by the complications of astrophysical processes. This leads
to a very clean prediction of the expected gravitational
wave profile one would observe from the merger, which is
in beautiful accord with what, has been measured (with a
signal to noise ratio of 24).
There are roughly three stages that can be seen in the
observed signal (Fig. 1 and 2). There is the initial inspiral
where the two black holes are mutually orbiting but
rapidly spiraling in towards each other. In this regime the
gravitational wave emission is modelled using the so-called
post-Newtonian approximation scheme, taken to fairly high
orders. Then there is the merger stage, which is a complicated non-linear regime of Einstein’s equations when the
two objects coalesce. Here the emission and its profile are
studied using numerical relativity techniques and matching
with the signal is a test of general relativity in the strong field
and non-linear regime. Finally, the last stage of emission
is from the small wobbles as the black hole settles into the
final Kerr solution. This is called the ringdown stage, like
the fading chimes of a bell that has been struck, and can be
studied analytically.
We can make an order of magnitude estimate of the time
scales involved in the ringdown since the only scale that
characterises the final black hole is the mass (if the angular
momentum is comparable to the mass, in appropriate
units, as appears to be the case here). According to general
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RESEARCH HIGHLIGHTS
relativity, a solar mass black hole (2x10^{30} kgs}) has a
Schwarzschild radius of about 3kms. Since the final black
hole involved in the event has a Schwarzschild radius of
~200 kms the time scale associated with the ring down is
t=R/c~10^{-3} secs. The merger that preceded it was over
a period of a few tens of milliseconds. The strong damping
in the ringdown signal is a signature of it being a black hole
and not a compact stellar body.
Gravitational Waves and Astronomy
Fig. 1.
Schematic illustration of the three stages of black hole binary
merger and the expected gravitational waveform (taken from P. Abbott
et.al. [1])
Fig. 2.
Comparison of the actual signals observed at the two LIGO
detectors with the expected waveform (taken from P. Abbott et.al. [1])
Fig. 3.
Supercomputer simulation of the merger of two black holes.
The expected gravitational-wave signal from this process is shown below.
(Photo source: SXS Collaboration/black-holes.org)
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Asia Pacific Physics Newsletter
Astrophysically, the significance of the LIGO observation
lies in it providing, for the first time, strong evidence for a
binary system of black holes, individually of several tens of
solar masses. Such systems were suspected to exist but had
not been “seen”. What had been seen were binaries of pulsars
slowly orbiting around each other and losing energy through
gravitational radiation. The expected decrease in their orbital
periods had been beautifully measured by Joseph Taylor over
several decades, on the binary system he had discovered
with Russell Hulse, thus indirectly confirming the existence
of gravitational radiation. But in their direct detection we
are already “seeing” new objects in the universe, which we
would, previously never have had access to.
Our telescopes have been seeing the universe, since
Galileo, with waves from the electromagnetic spectrum
like light, x-rays, radio waves and gamma rays. Such waves
are produced by the acceleration of electrically charged
particles. However, electromagnetic waves (like electric and
magnetic fields themselves) can be shielded! The main reason
being that electric charges can cancel to zero. A familiar
effect is microwaves being screened from emerging out of
the microwave oven! Thus the light from the primordial
universe before the era when it was an ionised plasma does
not make it to us! But gravitational waves can see farther
back in time and we hope to see signatures of their presence
in ongoing experiments. Besides there are likely to be many
dramatic phenomena like black hole mergers which are
not accompanied by electromagnetic radiation and hence
invisible to us. It is the prospect of overcoming both these
kinds of limitations to our sight that makes gravitational
wave astronomy exciting.
There are many different kinds of gravitational wave
observatories both current and planned. They range from
the two LIGO detectors and the VIRGO observatory in Italy
and planned ones in Japan and LIGO-India to the ambitious
space based eLISA. The instruments at these observatories
are Michelson type laser interferometers. (Alternative
methods for detection exist based on pulsar timing arrays
RESEARCH HIGHLIGHTS
and are sensitive to very low frequencies). Gravitational
waves from realistic astrophysical sources are very weak and
their wavelengths are from a few hundred to a few thousand
kilometers. When they pass through the earth they distort
the geometry of space-time and in particular affect the two
arms of the interferometer differently and that would be
presently detectable if we achieve a sensitivity that is one ten
thousandth of the size of the atomic nucleus! i.e. 10^{-18}
meters. This is why the interferometers have arms that are
approximately 4 km. long for LIGO and upto a million
km for the proposed eLISA. Efforts in perfecting the high
technology instruments are now on for nearly 2 decades.
LIGO operates in the frequency band 40-10,000 hertz and
aLIGO (advanced LIGO) operates down to 10 hertz. Because
these detectors are omnidirectional instruments it is hard
to localize the sources of the gravitational waves from just
one detector. This is why the presence of a third LIGO
detector somewhere in the eastern hemisphere is crucial
for gravitational wave astronomy. The good news is that the
Govt of India has given an in-principle approval for setting
up this facility in India. On 31st March this year, an MOU
was signed to this effect between the NSF and DAE-DST
for LIGO-India.
The LIGO Science Collaboration – is a worldwide
consortium of over 1000 scientists at about 90 institutions.
From the Asia-Pacific region, there are a total of sixteen
participating institutions. Of these eight are in India as part
of the IndiGo consortium, four from Australia and two each
from China and South Korea.
The IndIGO consortium, which has been doing the
spadework for LIGO-India, was formed in 2009 with B. Iyer
(currently at ICTS-TIFR, Bangalore) as chairperson and T.
Souradeep (IUCAA, Pune) as spokesperson. The establishment of this consortium and the push for LIGO-India is a
consequence of a strong historical tradition of gravitational
wave research in India. The ringdown phase that we
mentioned above was first calculated by C. V. Vishveshwara
in 1970. Gravitational wave signals from orbiting black
holes and compact objects were calculated by B. Iyer (then
at RRI, Bangalore) and his collaborators in France. Sanjeev
Dhurandhar working at IUCAA developed methods of dataanalysis to detect the weak gravitational wave signals buried
in noise. More recently P. Ajith (currently at ICTS-TIFR),
while a PhD student, developed a phenomenological method
for finding the waveforms of binary coalescing black holes.
The LIGO discovery will go down in history as the first
step towards a turning point in astronomy. Mankind can now
explore hitherto unknown and strange phenomena and in
the future (perhaps distant) astronomers would be able to
`hear’ the murmur or rumble of the universe in the remote
past after the big bang.
(Note: A version of this article has appeared in Current
Science, 10 April 2016 issue)
[1] Abbott, B. et al., Phys. Rev. Lett., 2016, 116, 061102.
Rajesh Gopakumar & Spenta R. Wadia
International Centre for Theoretical Sciences (ICTS-TIFR),
Tata Institute of Fundamental Research
Controlling Ultrafast Electrons in Motion
An international team has used the light produced by the
Free Electron Laser FERMI at the research Centre Elettra
Sincrotrone Trieste in the AREA Science Park to control the
ultrafast movement of electrons. The experiment, published
in the journal Nature Photonics, opens the way to the study of
more complex processes which occur in nature on the scale
of attoseconds (billionths of a billionth of a second), such
as photosynthesis, combustion, catalysis and atmospheric
chemistry.
Chemical, physical and biological processes are intrinsically dynamic, because they depend not only on the atomic
and electronic structure of matter, but also on how they
evolve in time. Ahmed Zewail won the Nobel prize (1999) for
"femtochemistry": the observation and control of dynamic
chemical processes using ultrafast laser pulses, of a few
millionths of a billionth of a second (femtoseconds). This is
the scale of time on which atoms make or break bonds in
Scheme of the experiment: pulses of light (waves) emit electrons (green)
from a neon atom (violet).
(Image courtesy of Maurizio Contran, Department of Physics, Politecnico
di Milano.)
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RESEARCH HIGHLIGHTS
chemical or biological processes, such as photosynthesis or
combustion.
Nature however can be still "faster". The atoms in a
molecule move on the scale of femtoseconds, but the electrons, which are the basis of chemical bonds, are much faster
and in the processes they cause, they move a thousand times
faster, that is, tens or hundreds of attoseconds (a billionth of
a billionth of a second).
"Like many in the scientific community", explains Kevin
Prince, first author of the article just published, "we have
also been working for years to develop innovative analytical
methods with attosecond resolution to study and control
fast dynamics. With this work, that exploits the exceptional
properties of the laser light from FERMI, we can say we have
finally achieved our goal."
The result was achieved by an international team of
researchers from Italy (Elettra-Sincrotrone Trieste, the
Politecnico of Milano, the IFN, IOM and ISM institutes
of CNR and ENEA), Japan (Tohoku University), Russia
(Lomonosov Moscow State University), USA (Drake University, Des Moines, Iowa) and Germany (Technical University
of Berlin, University of Freiburg, European XFEL, Hamburg,
Max Planck Institute for Nuclear Physics, Heidelberg).
They used a beam of light of two wavelengths (that is,
two different colours) and managed to control the direction
of emission of electrons ejected from an atom by the light.
The experiment had a time resolution of 3 attoseconds,
which now makes possible the study and control extremely
fast processes.
"This result opens a new avenue to study and control
ultrafast processes that involve electron motion on the time
scale of attoseconds. We are dreaming about controlling
more complex processes such as photocatalytic processes
where the charge transfer plays a key role" said Kiyoshi
Ueda, who with his group at Tohoku University, contributed
to planning and conducting the experiment, and analysing
the results.
Reproduced with permission from TOHOKU University.
Observation of High Temperature
Superconductivity without Effect of
Magnetism
A research group led by the University of Tokyo, performing
a process that removes oxygen impurities, has demonstrated
that high-temperature superconductivity emerges in copper
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Asia Pacific Physics Newsletter
oxides in a broader electron density region and at higher
temperatures than previously thought.
The phenomenon of superconductivity, by which electrons flow through a substance without electrical energy
being lost as heat energy, finds applications in maglev
trains, magnetic resonance imaging devices and the like.
Among superconducting materials, a group of copper
oxides in particular exhibit superconductivity at high
temperatures. However, the nature of superconductivity
that these substances demonstrate differs depending on
how the superconducting state was generated. Specifically, a
different superconducting state can be generated by adding
either negatively-charged electrons (“electron doping”) or
positively-charged electron holes to an insulating material
completely impervious to passing electricity. In particular,
oxygen impurities are easily incorporated into the crystal
structure of the material when creating a superconducting
state by electron doping, stabilizing what is termed an antiferromagnetic state, a kind of magnetism that was thought to
prevent the emergence of superconductivity.
Professor Atsushi Fujimori and graduate student Mr.
Masafumi Horio at the University of Tokyo, Graduate School
of Science, Department of Physics, and their colleagues
applied reduction-annealing, a type of heat treatment for
removing oxygen impurities, to a high-temperature copper
oxide superconductor created by electron doping. The group
then directly observed the electron state of the superconductor, and discovered that sufficient reduction-annealing
eliminates antiferromagnetism and enables the emergence
of a high-temperature superconducting state that is stable
over a much wider electron-concentration range and up to
a higher temperature than previously reported.
“This finding concerning the influence of antiferromagnetism induced by impurities on the superconducting state
challenges the conventional picture of the physics underlying
superconductivity, and calls for an experimental and theoretical reexamination of the phenomenon,” says Professor
Fujimori. He continues, “Thirty years have passed since the
discovery of copper oxide high-temperature superconductors, yet the mechanism by which superconductivity emerges
in these materials remains unknown. This outcome will
bring about a new approach to the study of the mechanism
of high-temperature superconductivity.”
This research was carried out in collaboration with
Professor Tadashi Adachi at Sophia University, Professor
Koike at Tohoku University, and the High-Energy Accelerator Research Organization (KEK).
The unique linear and nonlinear optical properties and
low losses make dielectric nanoparticles perfect candidates
RESEARCH HIGHLIGHTS
Changes in electronic structure induced by reduction annealing
Top: Fermi surface (contour surface of electron energy) before reduction
annealing (left) and band dispersion in direction of arrow (right). A band
gap, that is, an energy region where electrons do not exist, opens due to
antiferromagnetism. Bottom: Fermi surface of reduction-annealed sample
(left) and band dispersion in direction of arrow (right). The influence of
antiferromagnetism was eliminated and the band gap disappeared.
© 2016 Masafumi Horio.
for a design of high-performance nanoantennas, low-loss
metamaterials, and other novel all-dielectric nanophotonic
devices. The reported results will pave a way to establishing
novel efficient platforms of nanoscale resonant nonlinear
optical media driven by optically-induced magnetic response
of low-loss high-index nanoparticles.
Reproduced with permission from University of Tokyo.
Spin Dynamics in an Atomically Thin
Semi-conductor
Researchers at the National University of Singapore (NUS)
and Yale-NUS College have established the mechanisms
for spin motion in molybdenum disulfide, an emerging
two-dimensional (2D) material. Their discovery resolves
a research question on the properties of electron spin in
single layers of 2D materials, and paves the way for the next
generation of spintronics and low-power devices. The work
was published online in the journal Physical Review Letters
on 29 January 2016.
Molybdenum disulfide (MoS2), a class of transition metal
dichalcogenide compounds, has attracted great attention
due to wide recognition of its potential for manipulating
novel quantum degrees of freedom such as spin and valley.
Due to its unique material properties, a single layer of MoS2
has the potential to be used for spin transistors, where both
electric current and spin current can be switched on and off
independently. Despite this potential for application, there
have not been any experimental studies on the mechanism
for spin dynamics in MoS2.
To address this gap, scientists from the Centre for
Advanced 2D Materials at NUS used highly precise measurements of the classical and quantum motion of electrons
to extract information on how long spins live in this new
material.
The team of scientists led by Assistant Professor Goki Eda,
co-leader of this study who is from the NUS Department
of Physics and Department of Chemistry, thinned down a
crystal of molybdenite, a mineral of MoS2, to less than one
nanometer. Here, the electrons live in a purely 2D plane
that is just one atom thick. The researchers then successfully
injected a high density of electrons in this ultra-thin material
to enable measurements in the quantum mechanical regime.
Quantum transport measurements at low temperatures
of 2 Kelvin (-271 degrees Celsius) revealed a surprising
transition, where quantum mechanical wave interference
switched from constructive to destructive with increasing
magnetic field.
Mr Indra Yudhistira, a Research Associate with the NUS
Department of Physics who is under the supervision of
Assistant Professor Shaffique Adam, co-leader of the NUS
study who is from Yale-NUS College and NUS Department
of Physics, demonstrated that this crossover was caused by
spin dynamics.
By comparing the theoretical and experimental results,
the two research groups were able to extract spin lifetimes
and also determine that the relaxation was driven by the
Dyakonov-Perel type where electron spins live longer in
dirtier samples.
“Aside from investigating the fundamental properties of
low field magnetotransport in molybdenum disulfide, our
team was able to establish the mechanism for spin scattering
to reveal the properties of the electron spin,” said Dr Hennrik
Schmidt, who was a Research Fellow working under the
supervision of Asst Prof Eda when the study was conducted.
Commenting on the significance of the discovery, Asst
Prof Adam noted that spin-based devices would generally
lead to lower energy consumption as compared to conventional electronics. He explained, “The combination of MoS2
May 2016, Volume 5 No 2
67
RESEARCH HIGHLIGHTS
being a semiconductor and the long spin lifetimes open up
opportunities in spintronics, where the electron spin and
not the electron charge is used to transport information.
Such unconventional devices could allow for next generation
low-power devices.”
Professor Yoshihiro Iwasa, Director of the Center for
Quantum-Phase Electronics at the University of Tokyo,
and a world expert on quantum devices who first reported
superconductivity in this class of materials remarked, “2D
materials have been anticipated as a promising platform for
spintronics. I feel that this very comprehensive study of the
analysis of the electron spin life time will provide crucial
information for further pushing the research toward the
realisation of a new generation of spintronic devices.”
Reproduced with permission from National University of Singapore.
New Spectroscopy of 10ΛBe Hypernucleus
Redefines the Reference Data of Lambda
Hypernuclei
A team of international researchers has successfully measured precise binding energy of a 10ΛBe hypernucleus made
of four protons (ρ), five neutrons (n) and and a Lambda (Λ)
particle, at Thomas Jefferson National Accelerator Facility
(JLab), USA.
The research team, known as HKS Collaboration, consists
of 76 members from 21 institutes led by Tohoku University,
Hampton University and Florida International University.
All materials are made of small charged particles: nuclei
and electrons. A nucleus consists of protons and neutrons
that are bound by the nuclear force against Coulomb repulsion. Without the nuclear force, no material can exist stably.
Therefore, understanding it is essential to knowing how our
material world was created. A proton has positive charge
and a neutron has no charge. Therefore the Coulomb force
between proton-proton is repulsive and the Coulomb force
does not work between neutron-neutron. However, it is
widely known that the nuclear forces between proton-proton
and neutron-neutron are almost the same and this is one of
most basic features of the nuclear force. This is called as the
charge symmetry of the nuclear force.
Modern physics is trying to understand the nuclear force
as a part of a more general "baryonic force." A Lambda hypernucleus consists of a Lambda particle, the lightest baryon
with strangeness, in addition to protons and neutrons, so the
study of Lambda hypernuclei extends our knowledge of the
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Asia Pacific Physics Newsletter
nuclear force to the more general "baryonic force".
There have been long discussions about whether the
charge symmetry is also satisfied between Lambda-proton
(Λρ) and Lambda-neutron (Λn) systems. Recent experimental studies have revealed that the charge symmetry is
largely broken for light hypernuclei, 4ΛH and 4ΛHe [1,2].
Though its origin is still under debate, comparison of the
newly measured 10ΛBe binding energy with that of its mirror
hypernucleus 10ΛB shows small charge symmetry breaking
for heavier hypernuclei. Small charge symmetry breaking for
10
10
ΛBe − ΛB will shed light on the source of charge symmetry
breaking of the ΛΝ interaction. Furthermore, the existence
of 0.54 MeV shift is suggested for the reported binding energies of 12ΛC which has been serving as the mass reference for
various hypernuclei.
This shift would affect all reported hypernuclear binding
energies calibrated with 12ΛC and it has great impact on
hypernuclear study.
Reproduced with permission from TOHOKU University.
The magnetic spectrometers, HKS (High resolution Kaon Spectrometer)
and HES (High resolution Electron spectrometer) used for the experiment.
These spectrometers were constructed and tested in Japan and then
shipped to JLab. (Credit: Tohoku University)
The measured binding energy spectrum of 10ΛBe. Sharp peaks originating
from hypernuclei are clearlyobserved on accidental coincidence background and quasi-freely produced Lambda events.
OBITUARY
China's Accelerator Physicist
XIE Jialin (谢家麟) Dies at Age 96
X
IE Jialin, an expert in accelerator physics and technology and free electron lasers, a recipient of China's
top science award and Academician of Chinese
Academy of Sciences, died on February 20th at the age of 96.
Professor XIE was born in Harbin, Heilongjiang province
in August 1920. He graduated from Yanjing University in
1943 and moved to the United States for further study. At
Caltech, XIE obtained his M.S. degree in physics in 1948,
and in 1951 he received his PhD from Stanford University.
From 1951 to 1955, he worked at the microwave and
high-energy physics laboratory at Stanford University. He
was then in charge of building an accelerator at Michael
Reese Hospital in Chicago, which was the highest-energy (45
MeV) medical accelerator in the world at that time.
In 1955, Prof. XIE decided to return to China. Although
he faced many difficulties during that time, including a lack
of proper equipment and up-to-date information, and even
continuous exposure in a dangerous environment putting
his life in danger at times, Prof. XIE was determined to go
on with his research.
“These difficulties were nothing for someone who
wished to achieve something important,” he said. Following
successful prefabrication research on various components
of an electron linear accelerator, such as an electron gun,
accelerating tube, high-power pulse modulator, microwave
system and high-power klystron, he built a 30-MeV electron
linac in 1964, the first one ever built in China. The successful
construction of China’s first high-energy electron linear
particle accelerator led to Prof. XIE being awarded the Scientific and Technological Achievement Prize at the National
Science and Technology Conference in 1978.
During the 1980s, he headed the design, manufacture
and construction of the Beijing Electron-Positron Collider
Project. He later led the development of the Beijing Free
Electron Laser. He was elected to the Chinese Academy of
Sciences in 1980. In 1990, XIE was awarded a Supreme Prize
for National Science and Technology Progress.
On learning about the establishment of free electron
lasers around the world – the latest development in the field
of science and technology – XIE proposed the development
of the Beijing Free Electron Laser and then worked out a
concrete scheme. Using funds provided in 1987 under the
State 863 High Tech Program, he succeeded in building
China’s first infrared free-electron laser, which produced
spontaneous emission in May 1993; the lasing reached
saturation at the end of 1993. Following those built in the US
and western Europe, this was the first infrared free-electron
laser built in Asia. In 1994, he was awarded the Supreme Prize
for Science and Technology Progress by the CAS.
He has published over 40 scientific papers and several
specialized publications. As an associate professor in universities and institutes, Prof. XIE has mentored a great number
of accelerator physicists.
In 2015, the International Astronomical Union announced
that Minor Planet No. 32928 was named after Prof. XIE Jialin
to commemorate Prof. XIE’s outstanding contributions in
particle accelerator science. The Institute of High Energy
Physics established a Youth Innovation Fund which was
named the "XIE Jialin Fund."
Prof. XIE Jialin has long been at the forefront of accelerator science and technology research and made a great
contribution to the sustainable development of China's highenergy physics and particle accelerator research. Prof. XIE
is a role model for all science and technology workers, and
the XIE Jialin star in the sky will keep shining and inspiring
us long into the future.
Reproduced with permission from The Chinese Academy of Sciences.
(http://english.cas.cn/)
May 2016, Volume 5 No 2
69
CONFERENCE CALENDAR
Upcoming Conferences in the Asia Pacific Region
JUNE 2016
The 8th International Kasetsart
University Science and Technology
Annual Research Symposium
Date: 2 - 3 June, 2016
Location: Bangkok, Thailand
Organizers: Faculty of Science, Kasesart University
The International Kasetsart University Science
and Technology Annual Research Symposium
(I-KUSTARS) will provide an excellent international
forum for sharing knowledge and results in theory,
methodology and applications of Natural Science
and Applied Science. The symposium looks for
significant contributions to all major fields of
Science and Technology in theoretical and practical
aspects. The aim of the symposium is to provide a
platform for the researchers and students to meet
and share cutting-edge development in the field of
science and technology.
practitioners working in a wide variety of scientific
areas with a common interest in improving Power
Control and Optimization related techniques.
ICMMR 2016 3rd International
Conference on Mechanics and
Mechatronics Research
Date: 15–17 June 2016
Location: Chongqing, China
Organizers: ICMMR
2016 3rd International Conference on Mechanics
and Mechatronics Research (ICMMR 2016) is
the main annual research conference aimed at
presenting current research being carried out. The
idea of the conference is for the scientists, scholars,
engineers and students from the Universities all
around the world and the industry to present
ongoing research activities, and hence to foster
research relations between the Universities and the
industry.
Stochastic Processes in the Cell
Cycle
Date: 13 - 17 June, 2016
Location: Jerusalem, Israel
Organizers: Ariel Amir (Harvard University ),
Nathalie Q. Balaban (The Hebrew University) and
Naama Barkai (Weizmann Institute of Science)
14th International Symposium on
Nuclei in the Cosmos XIV
Date: 19–24 June 2016
Location: Toki Messe, Niigata, Japan
Organizers: National Astronomical Observatory
of Japan (NAOJ) and the RIKEN Nishina Center for
Accelerator-Based Science
The workshop will host a small group of scientists
from Physics, Mathematics, Biology and Computer
Science. By allowing significant amounts of time for
discussions rather than talks, we hope to encourage
the initiation of novel collaborations between the
participants, and a real exchange of ideas across
disciplines.
Nuclei in the Cosmos is the foremost bi-annual
symposium of nuclear physics, astrophysics,
astronomy, cosmo-chemistry, and other related
fields that started from Wien in Austria in 1990.
NIC-XIV http://nic2016.jp/ is jointly organized
by the National Astronomical Observatory of
Japan (NAOJ) and the RIKEN Nishina Center for
Accelerator-Based Science. It is sponsored by the
International Union of Pure and Applied Physics
(IUPAP), and supported by several institutions.
ICPCO 2016 2nd International
Conference on Power Control and
Optimization
Date: 15–17 June 2016
Location: Chongqing, China
Organizers: ICPCO
ICPCO conference is one of the leading
international conferences for presenting novel
and fundamental advances in the fields of Power
Control and Optimization. ICPCO also serves to
foster communication among researchers and
70
Asia Pacific Physics Newsletter
CLOUDY Workshop
Date: 20–24 June 2016
Location: Shandong, China
Organizers: Shandong University
The workshop will cover observation, theory, and
apply Cloudy to a wide variety of astronomical
environments, including the interstellar medium,
AGB stars, Active Galactic Nuclei, Starburst
galaxies, and the intergalactic medium. The
lectures and hands-on sessions will be carried
out by Gary Ferland. The sessions will consist
of a mix of textbook study, using Osterbrock &
Ferland, Astrophysics of Gaseous Nebulae and
Active Galactic Nuclei, and application of Cloudy.
Participants will break up into small teams and
organize research projects of mutual interest.
18th International Congress on
Plasma Physics (ICPP) – 2016
Date: 27 June–1 July 2016
Location: Kaohsiung Exhibition Center in
Kaohsiung, Taiwan
Organizers: Institute of Space and Plasma Sciences,
National Cheng Kung University, Tainan, Taiwan
The scope of ICPP is to discuss the recent progress
and to establish a view on the future of plasma
science, covering a wide range of aspects on
fundamental plasma physics, fusion plasmas,
astrophysical plasmas and plasma applications.
JULY 2016
OptoElectronics and
Communications Conference /
International Conference on
Photonics in Switching
Date: 3–7 July 2016
Location: Niigata, Japan
Organizers: Optical Society (OSA)
Topics of this conferece including, not limited too: 1.
Core/Access Networks and Switching Subsystems.
2. Transmission Systems and their Subsystems. 3.
Optical Fibers, Cables and Fiber Devices. 4. Optical
Active Devices and Modules. 5. Optical Passive
Devices and Modules. 6. Optical Switching System
and Related Technologies.
SUSY (Supersymmetry) 2016
Date: 4–8 July 2016
Location: Melbourne, Australia
Organizers: ARC Centre of Excellence for Particle
Physics at the Terascale (CoEPP)
The goal of the conference is to review and discuss
recent progress in theoretical, phenomenological,
and experimental aspects of supersymmetric
CONFERENCE CALENDAR
theories and other approaches to physics beyond
the Standard Model of particles and interactions.
SUSY is one of the world's largest international
meetings devoted to new ideas in fundamental
particle physics.
International Workshop on
“Fundamental Science and Society”
Date: 7-8 July 2016
Location: Quy Nhon, Vietnam
Organizers: the Ministry for science and technology
of Vietnam, the Popular Committee of the Province
of Binh Dinh, the “Rencontres du Vietnam” and the
“Rencontres de Moriond”
The workshop will be structured around round
tables addressing various historical, current and
future issues relevant to fundamental science
and society, with an opening up towards Asian
countries, in particular towards developing
countries around Vietnam and the themes proper
to them.
DAY 1: Science for the progress of knowledge and
for development, with presentations and round
tables on the role of fundamental research in
technological revolutions on the one hand, and in
sustainable development on the other hand.
DAY 2: Science for peace with presentations and
round tables on the themes of excellence, diversity
and of their underlying value on the one hand, and
of links between fundamental and applied research
in the framework of open innovation on the other
hand.
25th Annual International Laser
Physics Workshop
Date: 11–15 July 2016
Location: Yerevan, Republic of Armenia
Organizers: The annual international conference on laser
physics that took the name International Laser
Physics Workshop (LPHYS') has been established
in 1991 following the joint initiative of a group of
leading laser scientists in the former Soviet Union
under the leadership of Professor Alexander M
Prokhorov, a renowned Russian laser researcher and
a 1964 Nobel Prize laureate in physics.
25th International Conference on
Atomic Physics
Date: 24–29 July 2016
Location: Seoul, Korea
Organizers: -
The conference will present an outstanding
program of invited speakers and the topics
encompass forefront research subjects in the field
of atomic physics, such as precision measurements
(including atomic clocks and fundamental
constants), quantum optics and cavity QED,
ultracold atoms and molecules, Bose-Einstein
condensates, degenerate Fermi gases, optical
lattices, quantum computing with atoms and ions,
mesoscopic quantum systems, and ultrafast and
intense field interactions.
AUGUST 2016
33rd International Conference on
the Physics of Semiconductors
Date: 31 July –5 August 2016
Location: Beijing, China
Organizers: ICPS 2016 continues a series of biennial conferences
that began in the 1950's. ICPS is the premier
meeting for reporting all aspects of semiconductor
physics including electronic, structural, optical,
magnetic and transport properties. The conference
will reflect the state of art in the semiconductor
physics and will serve as a forum where scholars,
researchers, and specialists can interact to discuss
future research directions and technological
advancements.
Synthetic Topological Quantum
Matter
Date: 1–5 August 2016
Location: Beijing, China
Organizers: Kavli Institute for Theoretical Physics
China at the Chinese Academy of Sciences
The major objective of the KITPC/PKU conference
is to bring together leading researchers working
on the topological phases for ultracold atoms, as
well as condensed matter (and photonic) systems,
to report their latest findings in this area, and
investigate the new issues particularly connecting
to the interacting or non-linear systems. The main
topics of this conference include new experimental
and theoretical results of synthetic spin-orbit
coupling and gauge fields, quantum anomalous
Hall effect, topological superfluid, topological
flat band, Dirac and Weyl semimetals, topological
superconductors, topological insulators, and
topological Kondo physics.
Spin-orbit-coupled quantum gases
Date: 1–19 August 2016
Location: Beijing, China
Organizers: Kavli Institute for Theoretical Physics
China at the Chinese Academy of Sciences
It is a KITPC Program. Its main objective is to bring
together leading researchers working in a rapidly
developing area of Spin-orbit-coupling (SOC) for
quantum gases. In addition to leading theorists, the
Program will attract prominent experimentalists
working on the SOC, synthetic gauge fields and
related areas for ultracold atomic gases. This will
help to stimulate the work on the realization of a
new generation of experiments with SOC in Bose
and Fermi gases, in which the many-body effects
play an essential role.
IEEE International Conference on
Group IV Photonics
Date: 24–26 August 2016
Location: Shanghai, China
Organizers: IEEE
The conference will feature an exciting program
with presentations organized in three topical
sessions covering the breadth of Group-IV
photonic research and spanning the range from
scientific curiosity and fundamental discovery to
advanced applications and commercialization.
A special industry forum session is also planned
with solicited presentations from key industry
players in the field. Plenary presentations by
leading authorities of the international photonics
community will provide an insightful update on the
state of the world photonics R&D and market, and
address hot topics in the field.
ICOSM 2016 International
Conference on Sustainable
Materials
Date: 25–27 August 2016
Location: Chengdu, China
Organizers: ICOSM
The event has the objective of creating an
international forum for academics, researchers and
scientists from worldwide to discuss worldwide
results and proposals regarding to the soundest
issues related to MATERIALS.
May 2016, Volume 5 No 2
71
CONFERENCE CALENDAR
SEPTEMBER 2016
International Conference on
Molecule-Based Magnets
Date: 4–8 September 2016
Location: Sendai, Japan
Organizers: Tohoku University
The conference will feature the latest
developments in theoretical and experimental
quantum information science, feature talks by
leading international researchers, and provide
the opportunity for research discussions and
collaborations between international and Iranian
quantum information researchers.
ICMM is the largest conference related to the
molecule-based magnets. We anticipate fruitful
discussions on the latest topics during several
plenary, keynote, and invited lectures and poster
presentations. In addition, there will be pre- and
post-conferences for young researchers: “Rising Star
Symposium” and senior researchers.
26th International Nuclear Physics
Conference (INPC2016)
Date: 11–16 September 2016
Location: Adelaide, Australia
Organizers: Centre for the Subatomic Structure of
Matter at the University of Adelaide, the Australian
National University and ANSTO
International Conference of NearField Optics, Nanophotonics and
Related Techniques
Date: 4–8 September 2016
Location: Hamamatsu, Japan
Organizers: Shizuoka University
The Conference is organized by the Centre for the
Subatomic Structure of Matter at the University of
Adelaide, together with the Australian National
University and ANSTO. It is also sponsored by the
International Union of Pure and Applied Physics
(IUPAP) and by a number of organisations,
including AUSHEP, BNL, CoEPP, GSI and JLab. INPC
2016 will be held in the heart of Adelaide at the
Convention Centre on the banks of the River Torrens.
It will consist of 5 days of conference presentations,
with plenary sessions in the mornings, up to ten
parallel sessions in the afternoons, poster sessions
and a public lecture.
NFO has been held every second year since 1992
at Besancon, France and NFO is now the most
established and outstanding conference focused
on near-field optics, nanophotonics, plasmonics,
related techniques, and interdisciplinary network
of scientists. Following the tradition of NFO
conference, NFO-14 will provide great opportunities
for information exchange and creation of new
science and technologies.
International Conference on Highly
Frustrated Magnetism (HFM)
Date: 7–11 September 2016
Location: Taipei, Taiwan
Organizers: HFM
This international conference will be a great
opportunity for scientists from around the world to
share the most recent developments in the study of
frustration in magnets. It will feature presentations
reporting on experimental and theoretical studies
of magnetic frustration, in all of its manifestations.
International Iran Conference on
Quantum Information
Date: 8–11 September 2016
Location: Tehran, Iran, Islamic Republic of
Organizers: Sharif University of Technology
Tsinghua-NTU joint workshop on
Quantum Materials
Date: 19–20 September 2016
Location: Beijing, China
Organizers: Tsinghua University & Nanyang
Nanyang Technological University
Following the signing of the Memorandum of
Understanding by NTU and Tsinghua University
in 2007, the Tsinghua-NTU Joint Workshop on
Quantum Materials is the sixth in the series of
workshops organized by both universities to
strengthen the collaboration and promote synergy
between the two institutions.
The Singapore-China Joint Symposium on research
frontiers in physics is a traditional forum and has
become a regular event for physicists from China
and Singapore to present and discuss their latest
research advances in various fields of physics.
It is jointly organised by the Institute of
Advanced Studies (IAS) and School of Physical
and Mathematical Sciences (SPMS) at Nanyang
Technological University (NTU), the Physics
Department at the National University of Singapore
(NUS) and University of Science and Technology of
China (USTC).
2016 the 4th Int. Conf. on Optical
and Photonic Engineering (icOPEN
2016)
Date: 26–30 September 2016
Location: Chengdu, China
Organizers: icOPEN 2016
Following the success of icOPEN2015 in Singapore,
OPSS is proud to bring this well received conference
to Chengdu, China for the first time. icOPEN2016
will provide a timely platform to conduct a recap
of the latest technologies and industry milestones,
and promote optical and photonic engineering to a
wider audience.
NOVEMBER 2016
Aggregation Induced Emission
Date: 18–20 November 2016
Location: Guangzhou, China
Organizers: Royal Society of Chemistry
The themes of this conference includes New
and efficient fluorescent and phosphorescent
luminogens; Advance functional luminogens in the
solid-state; Biomedical applications of luminogens;
Optoelectronic devices of high efficient luminogens
in the solid state.
12th China Singapore Joint
Symposium on Research Frontiers
in Physics
Date: 22–24 September 2016
Location: Hefei, China
Organizers: NTU, NUS & USTC
APPN CONFERENCE CALENDAR welcomes conference information in the Asia Pacific Region.
To submit, send e-mail to [email protected]
72
Asia Pacific Physics Newsletter
JOBS
NON-MEMBER STATE POSTDOC FELLOWSHIP
PROGRAMME (THEORETICAL PHYSICS)
Work Location: Meyrin, Switzerland
RESEARCH FACULTY (ATOMIC PHYSICS AND
OPTICAL SCIENCE)
Company/Institute: CERN, the European Organization for Nuclear Research
Work Location: Taiwan
At CERN, the European Organization for Nuclear Research, physicists and
engineers are probing the fundamental structure of the universe. They use
the world's largest and most complex scientific instruments to study the basic
constituents of matter – the fundamental particles. The particles are made to
collide together at close to the speed of light. The process gives the physicists
clues about how the particles interact, and provides insights into the fundamental
laws of nature.
Company/Institute: The Institute of Atomic and Molecular Sciences in
Academia Sinica
The instruments used at CERN are purpose-built particle accelerators and
detectors. Accelerators boost beams of particles to high energies before the
beams are made to collide with each other or with stationary targets. Detectors
observe and record the results of these collisions.
Founded in 1954, the CERN laboratory sits astride the Franco-Swiss border
near Geneva. It was one of Europe's first joint ventures and now has 21
member states.
Job Description: The Non-Member State Fellowship Programme in Theoretical
Physics awards two postdoctoral fellowships per year. They are granted for two
years and can exceptionally be extended to a third year.
Requirements:
Applicants should NOT be a national of a CERN Member State. Nationals from
the CERN Member States (irrespective of their current place of study and/or
residence) should apply to the 'standard' Fellowship Programme (link is external).
Have a PhD in Theoretical Physics (or are about to finish your thesis) and are
looking for a postdoctoral position.
Have a maximum of 10 years of research experience after the degree which
gives access to doctoral programmes (MSc or equivalent).
How to apply:
The application and ALL supporting documents should reach CERN (or be
submitted using the e-recruitment system) by the closing date (15/10/2016).
Candidates should upload their documents such as their curriculum vitae,
publications, research interests etc. directly into our e-recruitment system
(e-RT). Recommendation letters can also be uploaded directly or sent to the
Recruitment Service by email, fax or postal mail (contact details are available
here). Candidates will receive an automatic email when these documents are
attached to their application.
Documents required
• a completed electronic application form
• a Curriculum Vitae
• a list of publications if relevant (for collaborations, please indicate simply
the number of publications and only provide details of the most important ones)
• a photocopy of the last (highest) qualification
• a short (half page) description of your motivation for coming to CERN
• three letters of recommendation to give as broad as possible overview of
your academic and/or professional achievements
• A short description of your research interests
74
Asia Pacific Physics Newsletter
In the early 1980s the founders of the Institute of Atomic and Molecular Sciences
(IAMS) had the vision to see the great potential of advanced instruments such
as high precision lasers and synchrotron radiation light sources together with
pulsed molecular beams, ionization techniques, and ultrahigh vacuum surface
techniques in elucidating the structures of atoms and molecules and the
dynamics and energetics of the interaction among atoms and molecules. They
proposed to establish an Institute to complement the research at the Institutes
of Physics and Chemistry in the Academia Sinica. A preparatory office was
initiated in 1982 headed by Dr. Chau-Ting Chang. Unfortunately in 1993 Dr.
Chang passed away unexpectedly at a young age. Dr. Sheng-Hsien Lin assumed
his responsibilities. In 1995 the Institute of Atomic and Molecular Sciences was
inaugurated as a full-fledged Institute in the Academia Sinica. Dr. Lin became the
first Director, from 1995-2001. Dr. Kopin Liu took the helm from 2001-2004.
Dr. Yuh-Lin Wang was appointed Director from 2004-2010. Dr. Mei-Yin Chou
is the current Director since 2011.
Under the vision and leadership of Dr. Yuan T. Lee, former President of the
Academia Sinica, and the previous Directors, the IAMS has grown to become a
multi-disciplinary center of excellence in fundamental research. Today, research
projects at the IAMS cover topics ranging from the spectroscopy and dynamics
of molecules to the fabrication and analysis of advanced materials to the study of
biophysics and the development of analytical tools for biomolecules. At present
the Institute has grown into a unit with 30 full-time Research Fellows and 11
Adjunct Research Fellows in the following four research groups: (1) Advanced
Materials and Surface Science, (2) Atomic Physics and Optical Science, (3)
Biophysics and Bio-analytical Technology, and (4) Chemical Dynamics and
Spectroscopy. There are over 200 visiting scientists, postdoctoral associates,
students, and research assistants working in the Institute, including about 90
master and Ph.D. students. The Institute is also an avid participant in the Taiwan
International Graduate Program (TIGP) within the Academia Sinica.
Job Description: One of the most prominent research institutes in Taiwan, the
Institute of Atomic and Molecular Sciences, Academia Sinica, invites qualified
candidates to apply for tenure track research fellow (PI) positions in the following
research fields: biophysical science, nano-science, surface science, molecular
dynamics, atomic physics, ultrafast and high-field optics, and interdisciplinary
field in physical chemistry or chemical physics.
Requirements:
Candidates at the Assistant, Associate, and Full Research Fellow (equivalent to
Assistant, Associate, and Full Professor) levels will be considered. They must
have a Ph.D. degree and will be expected to develop an internationally recognized
research program.
How to apply:
Applicants should send a full CV by air-mail or e-mail, including a list of
publications, a research proposal, and at least three letters of recommendation
to:
JOBS
Dr. Jung-Chi Liao, Room 202, P.O. Box 23-166, Institute of Atomic and Molecular
Sciences, Academia Sinica, Taipei, 10617, Taiwan.
E-mail: [email protected]; Fax: (886) 2-2362-0200.
ADJUNCT FACULTY (INTRODUCTION TO
APPLIED MATH AND PHYSICS)
Work Location: Singapore
How to apply:
To apply for this position, please complete the SIT Personal Information Form
and email together with your resume to [email protected].
POST-DOCTORAL RESEARCH FELLOW
Work Location: Suwon-si, South Korea
Company/Institute: Sungkyunkwan University
Company/Institute: Singapore Institute of Technology
The Singapore Institute of Technology (SIT) is Singapore's fifth autonomous
university. Established in 2009, the university primarily caters to local polytechnic
graduates who desire to pursue a bachelor's degree.
Vision
A leader in innovative university education by integrating learning, industry
and community.
Mission
To develop individuals who build on their interests and talents to impact society
by providing a nurturing environment that is uniquely enriched by world-class
partners.
Core Values
P: United in Purpose
R: Respect for Others
I: Uncompromising Integrity
D: Purposeful Dynamism
E: Relentless Pursuit of Excellence
Job Description: Module Synopsis: Introduction to Applied Math and Physics
We live in a world governed by physical laws. As a result we have become
accustomed to objects’ motions being in accordance with these laws. This course
examines the basic physics and mathematics governing natural phenomena, such
as light, weight, inertia, friction, momentum, and thrust as a practical introduction
to applied math and physics. Students explore geometry, trigonometry for cyclical
motions, and physical equations of motion for bodies moving under the influence
of forces. With these tools, students develop a broader understanding of the
impact of mathematics and physics on their daily lives.
Requirements:
The successful candidate must have a minimum of a master’s degree in an
appropriate discipline and have prior teaching experience. Our ideal candidate
must demonstrate an excitement about teaching, a commitment to student
success, and a pattern of active professional development.
For over six hundred years, Sungkyunkwan University has held an extraordinarily
special place in the history of Korea. Sungkyunkwan’s contributions to the
education and training of royal scholar-officials by preeminent Korean
philosophers have laid the foundation for numerous national advancements.
Since its establishment, the school’s educational tradition has emphasized the
four principles of benevolence, righteousness, propriety, and wisdom.
Sungkyunkwan University has also evolved to incorporate a modern educational
paradigm that prioritizes cutting-edge research and innovative education. This
has led to important advances in the arts, sciences, medicine, and technology
in ways that allow greater synergy with other leading universities and institutions
throughout the world.
Center for Integrated Nanostructure Physics (CINAP) located at Sungkyunkwan
University (SKKU) is founded in 2012 under the roof of Korea Institute for Basic
Science (IBS) which is established mainly to secure creative knowledge and
fundamental technology for the future through world-class basic science research
in Korea. The CINAP goals are to perform outstanding research in the fields of
fundamental and applied physics of low dimensional structures and to produce
young scientists committed to nanophysics and nanoscience.
Job Description: CINAP is particularly interested in the broad basic research
area of i) synthesis of 2D layered materials, ii) exciton dynamics and carrier
multiplication, iii) photo-thermoelectricity, iv) nanostructure analysis, v)
electrical/ optical/ magnetic measurements, and vi) computational modeling
of nanostructures. The CINAP seeks for post-doctoral fellows as part of its plan
to grow to a total of 60 research staffs.
Requirements:
Required qualifications include a doctorate degree in physics, chemistry,
engineering, applied physics or a related field. The successful candidate will be
expected to have strong written and oral communication skills in English, and
to perform independent IBS related researches, and to collaborate with other
groups in the CINAP.
How to apply:
Interested people should submit a letter of interest, a statement of research
interests, and current CV, and name and email of three or more references.
Submit your application package via e-mail [email protected] and cc to
[email protected] and all inquiries related to the positions address to (Tel) 8231-299-6507 and [email protected].
APPN JOBS accepts ads from organisations and individuals.
To submit, send e-mail to [email protected]
May 2016, Volume 5 No 2
75
SOCIETIES
List of Physical Societies in the Asia Pacific Region
South East Asia Theoretical Physics
Association (SEATPA)
President:Phua Kok Khoo
Address: Nanyang Executive Centre #02-18, 60 Nanyang View,
Singapore 639673
E-mail:[email protected]
http://www.seatpa.org
Association of Asia Pacific Physics Societies
President:Seunghwan Kim
Address: Asia Pacific Center for Theoretical Physics/POSTECH, 77Cheongam-Ro
Nam-gu, POSTECH, Pohang, Korea
E-mail:[email protected]
http://www.aapps.org
Australian Institute of Physics
President:Warrick Couch
Address: PO Box 546, East Melbourne, Vic. 3002
E-mail:[email protected]
http://www.aip.org.au
Bangladesh Physical Society
Indonesian Physical Society
President:Masno Ginting
Address: d/a Komplek Batan Indah Blok L No 48 Serpong Tangerang Banten
15314 Indonesia
E-mail:[email protected]
http://hfi.fisika.net
Israel Physical Society
President:Yaron Oz
Address: School of Physics and Astronomy, Tel Aviv University
E-mail:[email protected]
http://www.israelphysicalsociety.org
Physical Society of Japan
President:FUJII Yasuhiko
Address: Yushima Urban Building 8F, 2-31-22 Yushima, Bunkyo-ku,
Tokyo 113-0034, Japan
E-mail:[email protected]
http://www.jps.or.jp
Japan Society of Applied Physics
President:A. A. Ziauddin Ahmad
Address: Dhaka Dhaka 1216 Bangladesh
http://www.bdphs.org
President:Satoshi Kawata
Address: Osaka University
E-mail:[email protected]
http://www.jsap.or.jp
Chinese Physical Society
Korean Physical Society
President: Zhan Wenlong
Address: Institute of Physics, Chinese Academy of Sciences, Beijing 100190
E-mail: [email protected]
http: //www.cps-net.org.cn
Physical Society of Hong Kong
President:Ruiqin Zhang
Address: Department of Physics and Materials Science
City University of Hong Kong, Hong Kong
E-mail:[email protected]
http://www.pshk.org.hk
Indian Physics Association
President:S. L. Chaplot
Address: PRIP Shed, Room No. 4, B.A.R.C.,Trombay, Mumbai India 400085
E-mail: [email protected]
http://www.ipa1970.org.in
Indian Physical Society
President:Milan K. Sanyal
Address: IACS Campus, 2A&B Raja Subodh Chandra Mullick Road,
Kolkata 700032, India
http://www.iacs.res.in/ips
76
Asia Pacific Physics Newsletter
President:Y. P. Lee
Address: The Korean Physical Society, 635-4 Yeoksam-dong, Gangnam-gu,
Seoul 135-703, Korea
E-mail:[email protected]
http://www.kps.or.kr
Malaysian Institute of Physics
President:Kurunathan Ratnavelu
Address: INSTITUT FIZIK MALAYSIA (MALAYSIAN INSTITUTE OF PHYSICS)
C/O Jabatan Fizik, Universiti Malaya,
50603 Wilayah Persekutuan Kuala Lumpur, Malaysia.
E-mail:[email protected]
http://ifm.org.my/
Mongolian Physical Society
President:Orlokh Dorjkhaidav
Address: Institute of Physics and Technology
Enkhtaivan avenue 54b, Bayanzurkh district, Ulaanbaatar 13330,
Mongolia
E-mail:[email protected]
http://www.ipt.ac.mn/
SOCIETIES
Nepal Physical Society
Institute of Physics Singapore
New Zealand Institute of Physics
Physical Society of the Republic of China
President:Pradeep Kumar Bhattarai
Address: Tri-Chandra Multiple Campus, Ghanta Ghar, Ranipokhari,
Kathamndu
Email:[email protected]
http://www.nps.org.np
President:David Hutchinson
Address: Dodd-Walls Centre for Photonic & Quantum Technologies,
Department of Physics, University of Otago, PO Box 56,
Dunedin, 9054
E-mail:[email protected]
http://nzip.org.nz/
Pakistan Physical Society
President:M Zakaullah
Address: Room No 205, Technical Block, NCP, Islamabad, Shahdra Valley Road,
Islamabad 44000, Pakistan
E-mail:[email protected]
http://pps-pak.org/
Physical Society of Philippines
President:Romeric Pobre
Address: 3/F National Institute of Physics
University of the Philippines, Diliman 1101 Quezon City, Philippines
E-mail:[email protected]
http://www.spp-online.org/
President:Sow Chorng Haur
Address: Institute of Physics, National University of Singapore,
2 Science Drive 3, Singapore 117542
E-mail:[email protected]
http://www.physics.nus.edu.sg
President:Minn-Tsong Lin
Address: National Taiwan University, No.1 Sec. 4 Roosevelt Road,
10617 Taiwan
E-mail:[email protected]
http://psroc.phys.ntu.edu.tw
Thai Physical Society
President:Amon
Address: PO Box 217, Chiang Mai University, Muang District,
Chiang Mai 50202.
E-mail:[email protected]
http://www.thps.org
National Committee of Russian Physicists
President:Leonid V. Keldysh
Address: 119991 Moscow, Leninsky Prospekt, 32a
E-mail:[email protected]
http://www.gpad.ac.ru
Vietnam Physical Society
President:Nguyen Ba An
Address: PO box 607, Bo Ho, Hanoi, Vietnam
E-mail:[email protected]
http://www.iop.vast.ac.vn
May 2016, Volume 5 No 2
77
MEMORIAL VOLUME FOR
Y. NAMBU
edited by
Lars Brink (Chalmers University of Technology), Lay Nam Chang (Virginia Tech),
Moo-Young Han (Duke University) & Kok Khoo Phua (NTU, Singapore)
“I have only the fondest of memories of Nambu. He was a
man of inordinate kindness, and there were many times
that I felt I was a beneficiary of his consideration and
generosity. Of course, the impact of his science was
enormous.”
H. David Politzer, Caltech
Nobel Laureate in Physics, 2004
“A physicist universally admired by all who knew him as a
kind and caring friend who was modest, considerate and
soft-spoken. If Nambu is to be characterized in one short
phrase, it is that he was a person of humble modesty and
quiet dignity. But unbeknownst to many he also harbored
a delightful penchant for drama on one hand and a deep
sense of humor on the other.”
Moo-Young Han, Duke University
“As everyone knows, in 1960 Yoichiro Nambu
had the idea that the axial vector current
of beta decay could be considered to be
conserved in the same limit that the pion,
the lightest hadron, could be considered
massless [...] if the axial vector current was
associated with a spontaneously broken
approximate symmetry, with the pion playing
the role of a Goldstone boson. Nambu used
this idea to explain the success of the
Goldberger–Treiman formula for the pion
decay amplitude.”
Steven Weinberg, University of Texas at Austin
Nobel Laureate in Physics, 1979
200pp
Apr 2016
978-981-3108-31-8
US$48
£32
978-981-3108-32-5(pbk) US$28
£18
Statistical Mechanics
and Related Areas
Excursions in the Land of Statistical Physics
by Michael E. Fisher (The University of Maryland, College Park, USA)
A fundamental question in the theory of matter concerns the nature of different phases, the
transitions between them and the associated critical phenomena. The researches of Prof.
Michael Fisher address many aspects of these basic questions ranging from establishing
rigorous theorems for the underlying statistical mechanics through exact analytical and
precise numerical solutions for model systems, dimensional expansions and renormalization
group calculations, Monte Carlo simulations, and phenomenological and thermodynamic
analysis of concrete experimental observations.
386pp
Jul 2016
978-981-3144-89-7
US$88
978-981-3144-90-3(pbk) US$46
£56
£33
Chapter 1
Michael Fisher At King’s College London
Cyril Domb
Chapter 2
The Theory of Condensation And The Critical Point
Michael E. Fisher
Chapter 3
The States of Matter — A Theoretical Perspective
Michael E. Fisher
Chapter 4
Walks, Walls, Wetting, And Melting
Michael E. Fisher
Chapter 5
Condensed Matter Physics: Does Quantum Mechanics Matter?
Michael E. Fisher
Chapter 6
Phases and Phase Diagrams: Gibbs’s Legacy Today
Michael E. Fisher
Chapter 7
How to Simulate Fluid Criticality: The simplest ionic model has Ising
behavior but the proof is not so obvious!
Michael E. Fisher
Chapter 8
Molecular Motors: A Theorist’s Perspective
Anatoly B. Kolomeisky and Michael E. Fisher
Chapter 9
Renormalization group theory, the epsilon expansion and Ken Wilson as
I knew him
Michael E. Fisher
Chapter 10
Statistical physics in the oeuvre of Chen Ning Yang
Michael E. Fisher
World Scientific Series in 21st Century Mathematics - Volume 2
Fifty Years of Mathematical Physics
Selected Works of Ludwig Faddeev
edited by Molin Ge (Chern Institute of Mathematics, China & Chinese Academy of Science, China),
Antti J Niemi (Uppsala University, Sweden & CNRS/Tours, France)
“It is excellent.”
Nobel Laureate C N Yang
"Faddeev's selected papers give ample
evidence of his contributions at the
forefront of physics and mathematics.
The breadth, vigor and beauty of
Ludwig's permanent accomplishments
fully justifies calling him the 'Beethoven
of mathematical physics."
Professor Roman W Jackiw
(MIT)
Featuring exclusively the major scientific achievements of
Ludvig Faddeev that spans over fifty years of his career:
Part 1: Scattering Theory
Part 2: Automorphic Functions
Part 3: Field Theory
Part 4: Theory of Solitons
Part 5: Quantum Groups
Part 6: Knots
Part 7: General Questions
596pp
Apr 2016
978-981-4340-95-3
US$168 £111
978-981-3109-33-9(pbk) US$84
£55
Edu-renaissance: Notes from a Globetrotting
Higher Educator brings together 50 of Professor
Feng Da Hsuan’s speeches, articles and reviews
from the last decade and a half. They cover a
wide range of ever-relevant topics such as the
value of higher education in society, the role
Asian universities have in the world, and hot
topics like university ranking. Professor Feng
also shares his new ideas and insight on
promising young universities and higher
education in the 21st century. This volume is
ideal for readers who are part of a global
community concerned about one of the most
important issues in the world today — education.
by Feng Da Hsuan
460pp
Mar 2016
978-981-4632-70-6
US$55 / £36
978-981-31-4382-1(pbk)
US$29 / £20
“If universities are indeed the institutional Rosetta Stones of our
time, then Feng is arguably the sector’s Jean-Francois Champollion.”
C. David Naylor
President Emeritus, The University of Toronto
“This is a must-read book for all!”
Fu-Jia Yang
Academician, Chinese Academy of Sciences
Former President, Fudan University
Former Chancellor, University of Nottingham
“Professor Feng is a rare authority in linking higher educations
of North America and Asia, especially Greater China and Southeast
Asia.”
Sung-Mo Steve Kang
President, KAIST
Chancellor Emeritus, University of California, Merced
“A good book will leave a good taste in one’s mind. This is such a
book. Savor it!”
Professor Feng Da Hsuan is the Director of the Global Affairs
Office and Special Advisor to Rector at the University of Macau.
He is a fellow of the American Physical Society and an expert in
nuclear and nuclear astrophysics, quantum optics, and
mathematical physics, with a wide range of experiences and
outstanding achievements as a scholar, researcher, and leader of
university comprehensive development.
Professor Feng was M Russell Wehr Chair Professor of Physics at
Drexel University, Director of the Division of Theoretical Physics of the United States National Science Foundation, Vice President for research and economic development at the University
of Texas at Dallas, Vice President of the Fortune 500 Science
Applications International Corporation (SAIC), and Senior Vice
President of Tsing Hua University and Cheng Kung University
in Taiwan.
Shih Choon Fong
Professor and Former President, National University of Singapore
Founding President, King Abdullah University of Science and Technology
“I salute Professor Feng and congratulate him on the publication
of this vital and incomparable book, written by a true modern
Renaissance Man!”
Carter Tseng
Founder and CEO, Little Dragon Foundation
Member, Board of Directors, USA Committee of 100
Member, Board of Trustees, USA Give2Asia Foundation
“This ‘Edu-renaissance’ book by Da Hsuan Feng is a ‘tour de force’
of the 21st century fast-changing global academic world.”
Yitzhak Apeloig
President Emeritus
Technion-Israel Institute of Technology
O N T H E O C C A S IO N O F T H E 5 0 T H A N N IV E R S A R Y O F T H E R E N C O NT R E S D E M O RI O N D ,
T H E M I N I ST RY O F S C IE N C E A N D T E C H N O L O G Y O F V I E T N A M , T H E P O P U LA R C O M M I T T E E O F T H E
P R O V IN C E D E B I N H D I N H , T H E R E N C O N T R E S D U V I E T NA M AN D T H E R E N CO N T R E S D E M O R IO N D AR E
C O -O R G AN I Z I N G W I T H T H E P A R T N E RS H I P O F C E R N A N D T H E S O L V A Y IN S T I T U T E S A ND
U N D E R THE H IGH PA TR ON A G E OF UN E S C O
FUNDAMENTAL SCIENCE AND SOCIETY
ICISE, QUY NHON VIETNAM
7-8 JULY 2016
B A S I C R E S EA R CH A N D : – S U S TA I N A B L E D E V EL O P ME N T – P EA C E – C LI M A TE – H EA L TH – T H E
G L O B A L F A C I LI T A TI O N E D U C A TI O N , K N O WL E D G E A N D T EC H N O LO G Y M E CH AN I S M – O P EN
I N N O V A T I O N A N D C O L LA B O R A TI V E E CO N O M Y – T H E I M PO R T A N CE O F P U R S U I N G B A S IC
R E S E A R C H I N E ME R G IN G C O U N TR IE S
http://rencontresduvietnam.org/conferences/2016/fundamental-science-and-society/
Patronage Authorities
Vu Duc Dam (Vice Prime Minister of Vietnam), Chu Ngoc Anh (Minister of Science and Technology of Vietnam), Nguyen Quan (Former Minister of Science and
Technology of Vietnam), Nguyen Thanh Tung (General Secretary of the Province of Binh Dinh), Ho Quoc Dung (President of the Popular Committee of the Province of
Binh Dinh)
International Advisory Committee
Laurent Beaulieu (University Paris VI), Frederik Bordry (Director of Accelerators and Technology of CERN, Geneva), Jacques Dumarchez (University Paris VI), JeanMarie Frère (Université Libre de Bruxelles), Jerome Friedman (1990 Physics Nobel Laureate, MIT, Cambridge), Louis Fayard (CNRS, Paris), Yannick Giraud -Heraud
(University Paris VII), Serge Haroche (2012 Physics Nobel Laureates, ENS, Paris), Jacques Hassinski (University Paris 11, Orsay), Rolf Heuer (President of the German
Physical Society), Lydia Iconomidou-Fayard (University Paris XI), Jean Jouzel, (CEA, Saclay), Boaz Klima (Fermilab, Batavia), Pham Quang Hung (University of
Virginia, Charlottesville), Bolek Pietrzyk (Université Savoie Mont Blanc, Annecy), Carlo Rubbia (1984 Physics Nobel Laureate, CERN, Geneva), Trinh Xuân Thuân
(University of Virginia, Charlottesville)
International Scientific Committee
Jean Audouze (Former Scientific Advisor of President Mitterrand), Phan Thanh Binh (President, Ho Chi Minh City University), Lars Brink (Former Chair of Nobel
Committee for Physics, Göteborg), Hescheng Chen (Institute of High Energy Physics, Beijing), Pascal Colombani (Chairman of the Board of Directors of Valeo, Paris),
Michel Davier (Academy of Sciences, Paris), Jerome Friedman (1990 Physics Nobel Laureate, MIT, Cambridge), Fabiola Gianotti (General Director, CERN, Geneva),
David Gross (2004 Physics Nobel Laureate, Former Director of the KITP, Santa Barbara), Nguyen van Hieu (Former Director of National Center of Scientific Research,
Hanoi), Nguyen Duc Khuong (IPAG Business School, Paris), Pierre Léna (Academy of Sciences, Paris), Soo-Jong Rey (Seoul National University, Seoul), Dam Thanh
Son (University of Chicago, Academy of Sciences, USA), Neil Turok (Director of Perimeter Institute, Waterloo), Kurt Wüthrich (2002 Chemistry Nobel Laureate, ETH
and La Jolla)
[Date]
Steering Committee
Etienne Augé (Vice President, Université Paris XI, Orsay), Maurizio Bona (Advisor to the General Director, CERN, Geneva), Michel Spiro (President, French Physical
Society, Paris), Jean Tran Thanh Van (President, Rencontres du Vietnam, Gif sur Yvette)
Advisor to the Steering Committee
Marc Henneaux (Director, Institutes Solvay, Brussels)
Local Organizing Committee
Patrick Boiron (President of University of Science and Technology of Hanoi), Tran Chau (Vice President of the Popular Committee of Binh Dinh province), Huynh
Thanh Dat (Vice President of National University of Ho Chi Minh Ville), Nguyen Thi Thanh Ha (Vice Director of Social and Natural Science, Ministry of Science and
Technology), Tran Thi Thu Ha (Former Vice President of the Popular Committee of Binh Dinh province), Doan Minh Hoa (ICISE, Quy Nhon), Nguyen Viet Hung (Chief
of Staff of Vice Prime Minister), Phan Bao Ngoc (National University of Ho Chi Minh Ville), Le Cong Nhuong (Director of Science and Technology Department, Binh
Dinh, Quy Nhon), Tran Thanh Son (ICISE, Quy Nhon) , Nguyen Tan (Director of International Relation Department, Binh Dinh, Quy Nhon), Le Van Tang (Former
Director at the Ministry of Planning and Investment), Le Quang Thanh (Director of Social and Natural Science, Ministry of Science and Technology, Tu Diep Cong
Thanh
(National University
of Ho Chi Minh Ville), Bui Thanh Thao, National University of Ho Chi Minh Ville), Tran Thanh Van (ICISE, Quy Nhon)
Conference
Secretariat
Aimie Fong, Nguyen Thi Loi, Sarodia Vydelingum, Do Nghieng Thao
Sponsored by