Download Big Ideas in Science - University of Bristol

Big Ideas in Science
CHEM10001
20 Credit Points
Overview
This unit provides a broad introduction to some of the fundamental ideas in science. It
looks at the original ideas and concepts behind the discipline, the history and people
involved behind the main discoveries and inventions. By exploring some of the
fundamental ideas and concepts in science and combining these with a flavour of the
cutting edge of science research, the course aims to provide an inspirational insight
into science and real research at Bristol. The implications or consequences of the
ideas are explored as well as philosophical and ethical issues and the way different
important approaches have built upon each other or are interconnected. The remaining
unanswered questions and ongoing research into fundamental issues, with a particular
focus on research ongoing at the University will also be covered and the lectures are
supported and themes explored in the discussion groups.
Lecturers are from across the entire Faculty of Science (and beyond).
Lectures are held in Lecture Theatre 2 at 5pm in the School of Chemistry.
The Big Ideas – 2013/14 Programme
1.
Knowledge and Reality
2.
Complex Systems
3.
Planet & Climate
4.
Matter & Quanta
5.
Science & Society
6.
Symmetry
7.
Evolution
1st, 8th, 15th Oct 2013
22nd, 29th Oct, 5th Nov
12th, 19th, 26th Nov
3rd, 10th, 17th Dec, 28th Jan ‘14
4th, 11th 18th Feb
25th Feb, 4th Mar
11th, 18th Mar, 25th Apr
Big Idea 1. Knowledge and Reality
3 Lectures
Lecture 1: Reality & the Matrix in the Mind
Professor Bruce Hood (Psychology)
To have a big idea you need to have a brain in the first place. Brains evolved to enable
us to navigate and predict our world. To do so, we simulate the external world as an
internal model, which means that there is no direct access to reality. Rather everything
has to be interpreted and extrapolated. Those processes are efficient but not faultless.
At every level of the system, there are consistent biases, distortions, and illusions that
reveal how our brain and the mind it creates is constrained to interpret the world in
certain ways. In this lecture we will examine the neuroscience of thought processes
and the way that the brain handles information.
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Lecture 2: To Infinity and Beyond
Dr Richard Pettigrew (Philosophy)
One of the biggest ideas in mathematics in the last two hundred years is that infinity
comes in different sizes. The so-called counting numbers -- i.e. 0, 1, 2, 3, 4, 5, etc. -are used to say how many things there are in a particular finite set of objects, such as
the set of students on this course, or the set of words on the page you're reading. But
what can we say when the set we're interested in has infinitely many things in it?
Take, for instance, the set of counting numbers itself. Is there a number we can use
to say how many counting numbers there are? Or must we just say of all such sets
that they are infinite? The answer is that there are special numbers we can use. They
are called the transfinite numbers. In this lecture, we'll be exploring the strange world
of these transfinite numbers. We'll find out which transfinite number attaches to
which familiar infinite sets. And we'll encounter basic questions about these numbers
that still baffle mathematicians.
Lecture 3: Pure Mathematics and Big Ideas in Science
Professor Jon Keating (Mathematics)
We will discuss the remarkable role played by Pure Mathematics in developing some
of the Big Ideas in Science. More generally, we will also discuss the position of
Mathematics as a language for, and a tool used in Science. Some of the ideas
described in Wigner's famous essay: The Unreasonable Effectiveness of Mathematics
in the Natural Sciences.
Big Idea 2. Complex Systems
3 Lectures
Complex systems defy our attempts to model them precisely. Sometimes this is
because we lack the computing power to resolve all of the interesting scales of
activity (e.g. atmospheric modelling, for weather forecasting). More often, though, it
is because we lack the theoretical understanding necessary to describe all of the
subsystems, and the ways in which they interact. Furthermore, where we have
measurements, they tend not to span all of the scales at which the system and its
subsystems operate.
Complex systems are interesting for their own sake, but they also occur at the heart of
many of society’s most pressing policy issues, such as the behaviour of financial
markets, energy demand, supply, and distribution, environmental regulation, and
climate prediction and climate change adaptation. The challenges of predicting and
regulating complex systems has lead some people to define a new mode of science:
‘post-normal science’.
These three lectures provide a brief introduction to the scope and challenges of the
scientific analysis of complex systems, discussing the interplay of theory, empirical
modelling, hypothesis testing, and uncertainty assessment, with examples taken from
ecology, biology, and environmental science.
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Lecture 1. Social self-organisation
Professor Nigel R. Franks (Biological Sciences)
A complex system is one that is more than the sum of its parts. Naturally, biology is
where complex systems are at their zenith. Indeed, the great evolutionary transitions,
e.g. the origin of (a) chromosomes, (b) eukaryotic cells, (c) multicellular organisms
and (d) animal societies, are all characterized by the collaboration or fusion of
existing entities into new conglomerates. “More than the sum of its parts” might
sound mysterious or even mystical. Not so: all this means is that the way the parts
interact with one another generates new properties at a higher corporate level.
Understanding complex systems requires virtuous cycles of experimentation and
mathematical modelling. Social insect colonies are a manifestation of the last great
evolutionary transition – they are super-organisms composed of separate organisms.
This means that they are ideal experimental systems for understanding complexity
because they can be taken apart and put back together again and most of the key
interactions among their components are macroscopic and visible. Here, I will
describe experiments that show, for example, how whole social insect colonies, e.g.
ants and bees, can solve problems beyond the scope of their individual members –
much as brains are more sophisticated than their individual neurones.
Lecture 2. Molecules, Cells and Organisms
Professor Claire Grierson (Biological Sciences)
Organisms are groups of cells that have found ways to live closely together. Cells are
groups of molecules that self-organise into structures that sustain life. Microscope
techniques enable us to see cells and tissues at unprecedented levels of detail.
Mathematical and computational models help us to understand what we see. We will
consider how molecules self organise so that one part of a cell can grow whilst the
rest of the cell does not, how cells find out where they are in tissues so they know
when to specialise, and how cells organise themselves into intricate structures.
Lecture 3. The Biology of Cancer
Professor Paul Martin (Biochemistry) and Professor Catherine Nobes (Biochemistry)
Cancer is one of science’s great mysteries. In this lecture will introduce the cell and
molecular biology of cancer cell progression towards a tumour and its subsequent
metastatic spread to other tissues and organs of the body. We will provide an insight
into how science is leading us towards novel therapeutic strategies for fighting the
ever-evolving cancer cell enemy.
Big Idea 5. Planet & Climate
3 Lectures
Lecture 1: Climate Change: Can Science and Technology Save us?
Professor Richard Pancost (Chemistry)
Climate change is rarely out of the public headlines yet there appears to be continued
controversy over the science. Is it a key issue for our times or the biggest science
fraud in history? The lecture will review the science behind the headlines, and discuss
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those aspects of the science that we are confident in and those for which the
uncertainty is higher. It will cover the evidence for past climate change, and the
techniques used to predict the future evolution of climate. The balance of evidence
supports the premise that climate is changing due to our activities and that there will
be substantial changes to our environment in the future. So the subsequent question is
whether this change is dangerous and whether there is anything that science can do to
help solve the problems.
Lecture 2: Climate impacts and policy: risk, data, models and inference.
Professor Paul Bates (Geographical Sciences)
What will be the impact of climate change? Will climate change cause more extreme
storms, floods and droughts in the future, and will we even be able to observe such a
change if it happens? These are some the key questions currently faced by climate
scientists, and whilst the impact of humans on global mean temperatures is now
accepted being able to say what this will mean for more relevant quantities is much
more difficult. There are a number of reasons for this. First, change is felt at
regional and local scales and here models may not even agree on the sign of the
change. Second, extreme events are rare by their very nature and determining
whether there has been a statistically significant increase in events that happen
perhaps just once in a hundred years is problematic. Lastly, the earth system is
distinctly non-stationary so the idea that there is a baseline for very rare events is
almost certainly a fallacy. This lecture will examine how uncertain models are used
with limited, sparse and uncertain data to make policy. It will aim to show that a risk
based framework is essential for robust science and policy inference and illustrate this
through a range of climate and hazard modelling examples.
Lecture 3: From Volcanoes to Vineyards: how lava flows shape the landscape
Professor Katharine V. Cashman (Earth Sciences) &
Dr Caroline Williams (HiPLA Studies)
Basaltic lava flows cover much of the Earth’s surface, as well as the surfaces of the
other terrestrial planets; thus basalt forms the substrate of many volcanic landscapes
(and, often, associated vineyards). The frequency of lava flow activity both threatens
nearby communities and provides unique opportunities for volcanologists to study
active volcanic processes. For this reason, two of the earliest volcano observatories
were founded at volcanoes with frequent lava flow activity (Vesuvius, Italy, in 1841;
and Kilauea, Hawaii, in 1912). These dual motivations – hazard and opportunity –
have also made locations of frequent lava flow activity the focal point for testing and
applying new innovations in volcano monitoring technology, particularly new
methods of remote sensing. I will review some of these new techniques and place
their contribution in the context of the challenges associated with monitoring and
predicting lava flow behavior, which relate not only to the high temperatures and
spatial extents of active flows, but also to their dramatic changes in physical
properties during emplacement (from liquids with included gas bubbles to dense
solids). Remote sensing observations are also providing us with new perspectives on
the post-emplacement evolution of basaltic landscapes, including both their unique
hydrological characteristics and key controls on flow revegetation.
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Big Idea 4. Matter & Quanta
4 Lectures
Lecture 1: The Periodic Table
Professor Nicholas Norman (Chemistry)
The Periodic Table of the Elements is perhaps the most important organising principle
in all of chemistry and its development in the latter half of the 19th century provides a
fine example of the scientific method at work. Empirical observations and deductive
reasoning led to a model from which predictions could be made that were testable by
experiment or further observation. Confirmation of the predictions soon followed but
it was not until the early 20th century that the nascent quantum theory allowed a more
thorough understanding of why the Periodic Table has the form that it does. To this
day, however, arguments persist as to the best way to represent it graphically.
This lecture will look at all aspects of the Periodic Table from its birth, to its impact
on the development of quantum theory, to modern day controversies about where best
to place new super-heavy elements.
Lecture 2: Bright Earth: The Invention of Colour
Professor Philip Ball
One of the often neglected components of art is what it is made from: paint. Where
did artists get their colours from, and how have changes in the repertoire of colours
over the ages affected the way that artists paint? Today, when there are masses of
colours available off the shelf in art shops, we tend to take them from granted, and it
is easy to forget that these colours had to be invented, one by one, in what was
sometimes a painstaking process. Artists of earlier times had a much more limited
palette, and some of their colours were immensely expensive, while some were
unstable and tended to fade or darken. In order to make their materials and put them
to the best use, painters once had to be chemically literate. I will trace the chemical
history of the pigments on the artist’s palette, and show how the invention of new
colour has constantly transformed art.
Lecture 3: Quantum mechanics
Professor Sandu Popescu (Physics) & Professor Jeremy O’Brien (Physics)
Quantum mechanics describes the behaviour of small particles, such as atoms,
electrons, molecules and so on; by extension, since everything is made of small
particles, quantum mechanics is supposed to describe the entire physical world. But
the behaviour of small particles is extremely unusual, even paradoxical, and defies
our intuition which is built by observing the world of big objects that surround us.
In the first part of the lecture we will present the basic ideas of quantum physics by
analysing the most typical example of quantum behaviour: two-slit interference
experiment with electrons. In particular the most paradoxical aspects will be
discussed: that a particle does not have a position unless we do not look at it, that
when we know where a particle is we cannot know its speed and vice-versa and the
ideas that Nature is fundamentally probabilistic and non-local.
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The theory of quantum mechanics was developed at the beginning of the twentieth
century to better explain the spectra of light emitted by atoms. At the time, many
people believed that physics was almost completely understood, with only a few
remaining anomalies to be ‘ironed out’. The full theory of quantum mechanics
emerged as a completely unexpected description of nature at a fundamental level. It
portrays a world that is fundamentally probabilistic, where a single object can be in
two places at once—superposition—and where two objects in remote locations can be
instantaneously connected—entanglement. These unusual properties have been
observed, and quantum mechanics remains the most successful theory ever
developed, in terms of the precision of its predictions. Today, we are learning how to
harness these surprising quantum effects to realize profoundly new quantum
technologies. This lecture will examine how single particles of light—photons—are
being used to develop secure communication systems based on the laws of physics,
precision measurements using entangled light, and information processors that
promise exponentially greater computational power for particular tasks.
Lecture 4: Quanta Research Edge – the Little Big Idea
Professor Mervyn Miles (Physics)
Quantum mechanics was at the heart of a new microscopy that could visualize
individual atoms and molecules. Actually, it does better than this and can visualize
molecular orbits associated with the atoms. The technique is based on quantum
mechanical tunnelling of electrons between a sharp conducting probe scanning over
the sample surface. It is called scanning tunneling microscopy (STM). STM can also
be used to manipulate individual atoms into particular arrangements including
assembling a molecule.
With the invention of STM’s close relative, the atomic force microscope (AFM), the
restriction of being able to image only conducting samples disappeared. AFM
visualizes the surface topography of the sample by measuring a force interaction
between it and a sharp tip. AFM is particularly versatile for biomolecular samples
because it can operate in liquids. One of the most spectacular implementations of
AFM allows subatomic imaging of atoms such that the internal distribution of
electrons is seen.
Learning Objectives
• Historical appreciation of the Periodic Table
• Understanding of the basis of its structure
• Appreciation of the Scientific Method at work and how empirical evidence
implies the existence of atomic structure
• Discuss how quantum mechanics can be used to understand the periodic table
• Articulate how quantum mechanics, together with the heaviness of nuclei
compared to electrons, justifies the concept of molecular structure
• Understand that the quantum physics can be harnessed for new functionality
and improved performance in future information and communication
technologies.
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Understand the basic ideas of quantum communication, metrology and
computation.
Appreciate the ways in which these technologies are being developed with
photons.
Understand how quantum tunnelling is used to image atoms and molecules
and quantum phenomena.
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Big Idea 5. Science & Society
3 Lectures
Lecture 1: Science and Society
Professor Kathy Sykes & Dr Kate Miller
Over the last few decades, there has been a growth in ‘public engagement with
science’. In 2000 a celebrated report by the House of Lords Science and Technology
Committee, called ‘Science and Society’ marked a turning point, where the emphasis
changed from trying to demand that the public understand science, and instead asked
that scientists understand the public better. Many funders of science are now trying to
incorporate public thinking into how they make decisions about what to fund in
science, especially in areas which might have profound impacts on the public, like
Geoengineering, Synthetic Biology and Nano-technologies.
This lecture and discussion will: explore the changing relationship between science
and society; describe how science is funded and how that is changing and ask what
might be expected of future scientists, in how they work and how they talk with, and
listen to, the public.
Learning Objectives
• Gaining an overview of how public engagement in science is changing
• Understanding of how science is funded and how that is changing
• Reflection on why and how scientists should engage with the public
• Appreciation that the public’s views (and others) need considering and
respecting, even if one does not agree with them.
Lecture 2: Public Engagement (TBC)
Dr Rachael Gooberman-Hill
In this session we will explore examples of co-produced research - where members of
the public are collaborating with researchers right from the start of the research
process. This approach is growing here at the University of Bristol and is something
that many funders of science are encouraging. Rachael Gooberman-Hill from the
School of Clinical Sciences will share her experience of several projects in which the
public have had a real say about the direction of the research. She'll describe working
with the public to design elements of research ranging from a 'placebo' (sham)
intervention to large-scale clinical trials.
Lecture 3: Science Communication and the Media
Professor Paul Valdes and Fiona Lethbridge (Press Officer at the Science Media
Centre). Chaired by Professor Kathy Sykes
The media is claimed to be the main way that members of the public learn about
science once they have left school. There are great opportunities - and some hazards in talking with the media about science.
This discussion will explore the opportunities and risks of talking with the media
about science. Some of the impacts will be explored, of both talking with the media,
and not talking with them when science is in the news. Reasons to engage will be
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explored, as well as ways to do it well, given the constraints that people in the media
are working under. There will be some consideration about ways of handling
scientific uncertainty, when interviewers often want ‘facts’.
Learning Objectives
• Reflection on the role of the media in science and society
• Increased appreciation of how scientists interact with the media, and reasons
for (and against) doing it
• An appreciation of some of the constraints that people in the media work
under
Big Idea 6. Symmetry
2 Lectures
Symmetry is one of the most powerful unifying principles in our understanding of
nature. Symmetry principles not only let us organize and classify our observations,
but have often provided the intellectual signposts to new predictions and discoveries.
In this module, we will investigate the mathematical language of symmetry; discover
how symmetry principles lie behind the most fundamental physical laws; and discuss
how complex systems without explicit symmetry can be understood.
Lecture 1: Perfect Symmetry
Dr Nina Snaith (Mathematics)
Symmetry appeals to humans for aesthetic reasons. Visually we find symmetric
objects beautiful, and in the same way a mathematician will favour an elegant,
balanced explanation over one that just gets the job done. But symmetry is also
appealing because it is useful; it is easier to see something is missing or incomplete if
there is a symmetry to the picture.
We will talk about what symmetry means in mathematics. We will examine cases of
how the symmetries in a problem have led mathematicians to make ground-breaking
advances that develop the mathematical tools and language that are invaluable in
other areas of science and technology.
Lecture 2: Continuous symmetries and the laws of physics
Dr Mark Dennis (Physics)
The universe is a very symmetric place: mostly, experiments into the laws of nature
have the same results, regardless of where, when or in which direction you do them.
Building on the previous lecture focusing on symmetry in maths, we will see how
this is related to the continuous symmetry inherent in the structure of space and time,
and how from this, we can understand the laws of conservation of energy and
momentum, fundamental to modern physics. We will also see how generalizations of
these ideas lead to the conservation of electric charge and more exotic quantities
associated with fundamental particles, currently investigated in high-energy
experiments such as the LHC at CERN.
Learning objectives:
• Basic knowledge of what symmetry can mean in mathematics
• Appreciation that ideas of symmetry have lead to major advances in
mathematics
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Appreciate continuous symmetries at the heart of physical experiment.
Understand the link between conserved quantities and continuous symmetries
at a basic level.
See how questions of symmetry underpin contemporary large-scale physics
experiments such as CERN
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Big Idea 7. Evolution
3 Lectures
Lecture 1: Evolution
Professor Michael J. Benton (Earth Sciences)
Evolution is strongly associated with the name of Charles Darwin who, in 1859,
published his views in ‘On the origin of species’. Today, after more than 150 years,
his ideas have themselves evolved and crystallized, and they have stood the test of
time. Knowledge of science in Victorian times was enough to make the case; the
addition of genetics and molecular biology in the twentieth century further confirmed
the validity of what he said.
In this lecture, we will introduce Darwin, review the key points of his writings, and
then bring the theme up-to-date, highlighting the nine key lines of evidence for
evolution, namely: (1) Evolution can be observed in nature; (2) Evolution can be
produced experimentally (e.g. artificial selection); (3) Natural species show extensive
variation; (4) New species can be produced experimentally; (5) Small-scale
observations can be scaled up; (6) There are homologous similarities between groups
of living things; (7) Different homologies are correlated and can be hierarchically
classified; (8) There is fossil evidence for transformation of species; (9) The order of
major groups in the fossil record suggests evolution.
Lecture 2: Creationism
Professor Innes Cuthill (Biological Sciences)
Humans and all other living things evolved; their existence is entirely explicable by
mechanistic, non-supernatural forces acting under the normal laws of physics. That
science has explained one of the oldest questions in philosophy – why am I here? – is
a remarkable achievement, with profound implications. Modern theologians reconcile
the seemingly insurmountable contradiction with religious accounts of Creation by
accepting that the latter are myths, with the spiritual and moral messages packaged in
terms that are understandable to a lay audience and, at the time the passages were
written, made sense of seemingly mysterious patterns in nature. Yet today, a vocal but
powerful minority of religious extremists persist in denying evolution and propagate
Creationist accounts through distortions of the scientific facts, alternative pseudoscience such as ‘intelligent design’, and an appeal to liberal sentiments about free
speech. While biblical literalism might be easily dismissed as a lunatic fringe, there is
undeniably widespread confusion over evolution, the scientific facts supporting it, and
the nature of scientific explanation in general. As scientists, you will be challenged on
this at some point, and will be expected to have access to the facts. This lecture aims
to give you the intellectual tools to arrive at an informed personal opinion and to
educate others on this profound issue.
Lecture 3: Unnatural Selection
Professor Gary Foster (Biological Sciences)
The human race has been applying ‘unnatural’ selection on many aspects of nature for
many years; it is not a new development. With the advent of genetic engineering the
process just became more precise and rapid, but also more controversial.
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Controversial as with the advent of genetic engineering, or genetic modification,
barriers on gene flow were removed and opportunities to modify and thus ‘evolve’
became almost limitless. So where will unnatural selection and evolution lead us in
the future?
In this lecture, we will introduce genetic engineering or ‘unnatural’ selection, initially
using GM crops as a well-advanced system to explain why the technology was
developed and implemented, what it can achieve, and just as important the
controversy that surrounds it. We will also examine as the technology advances what
will be next for full genetic engineering, with animals already well under way, will
humans be next. Is science fiction becoming science fact? Will genetic disorders be
corrected, could eye color be selected, and what are the possibilities of extending life
spans for humans.
Learning Objectives
• Appreciation of the wide range of phenomena that evolution, and only
evolution, can explain
• Knowledge of the key evidence for evolution from morphology, embryology,
palaeontology, biogeography and genetics
• Historical appreciation of development of ideas of evolution
• Appreciation of the distinction between evolution, the historical pattern, and
evolution, the mechanisms generating change
• Evolution as a case study for how broad-scale theories are assimilated and
tested
• Common misunderstanding about, and misrepresentations of, evolution
• An understanding of the possibilities through the application of genetic
engineering
• Appreciation of the controversies surrounding GM technologies, as well as the
advantages
• Knowledge of the key developing technologies with GM and where this may
lead, and the related ethical and moral implications
PJW Oct 2013 v6
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