see flyer - Centre for Research in String Theory
... "The strong nuclear force binding the nucleus is described very well by Quantum
Chromo-Dynamics (QCD) which has been directly tested in high energy collisions of
elementary particles. However, extracting quantitative predictions from QCD for low
energy or macroscopic phenomena is one of the outstand ...
... The main conceptual changes in understanding the physical world that were discovered in the twentieth
century are presented. Starting with the introduction of the quantum of light by Planck in 1900 and
ending with the standard models for cosmology and particle structure as we understand them now.
Questions on The Elegant Universe 1. What was Einstein`s dream
... 2. What is the new theory attempting to answer Einstein’s dream and what does it propose?
♦ An all encompassing and unifying theory that combines all the laws of the universe called
“String Theory.” The basic idea of string theory is surprisingly simple. It says that
everything in the universe, from ...
... Theory only works when gravity is ignored (very
General Relativity only works when we can
assume the universe can be described by
classical physics (no quantum mechanics)
The Universe itself
... astrophysical observations, is being made6.
Much purely theoretical work is
usually focused on finding an answer to
what happens at the Planck scale: masses,
lengths or times where the strength of
gravity becomes comparable to the other
fundamental interactions (which are
currently unified in the st ...
Byond Particle Physics
... The history of supersymmetry is exceptional. In the past, virtually all
major conceptual breakthroughs have occurred because physicists were
trying to understand some established aspect of nature. In contrast, the
discovery of supersymmetry in the early 1970s was a purely intellectual
achievement, d ...
Desperately Seeking Superstrings
... right stuff to explain the “low-energy phenomena” of high-energy physics and gravity as
well. In the context of possible quantum theories of gravity, each of the few currently
known superstring theories may even be unique, finite and self-consistent. In principle a
superstring theory ordains what pa ...
Dalton`s Atomic Theory
... Dalton's Atomic Theory
Earlier we used the Particle theory of Matter to explain observations
of matter. However, this theory cannot explain everything we have just
learned regarding chemical changes.
For example it cannot explain the electrolysis of water.
Física Teórica de Partículas
... Is there Supersymmetry? If yes, where is it hidden?
Dark Matter ?
Quantum Gravity ?
All fundamental laws of Nature must obey the !
Principles of Quantum Mechanics.
Einstein ´s General Relativity is a beautiful Classical
Theory, like Maxwell´s Classical Theory, neither one is a
... Also, we tried to limit the material to the
essential parts of a very difficult subject: many deep and wonderful technical results of the theory had to be omitted because they concerned ‘internal’
matters, and would not be appreciated
by outsiders. This severe self-discipline
made the book accessibl ...
Using Boolean Logic to Research Quantum Field Theory
... The Stanford Encyclopedia of philosophy recognizes Quantum Field Theory as mathematical and
conceptual framework that implements elementary particles in particle physics. This also acquired the
theory as a sub subject of both Quantum Physics and Particle Physics. Stanford University uses those
... describe certain aspects of nature. The
first Theoretical Physicist was Sir Isaac
Newton. Newton invented Calculus so
that problems involving moving objects
could be solved.
Journey into the Microcosm – The Story of Elementary Particles
... entities mankind has probed, has attained a stage where there is a ‘standard
model’ – a God of small things, so to
speak – in excellent agreement with
experiments, so much so that any tiny
deviation, for example, a small non-zero
neutrino mass, is considered a major
breakthrough. There is no competi ...
... & all matter
Modern view of matter and the universe
... (Standard Model + GUT)
• We can unified electromagnetic, weak and
• (But) We don’t understand why there are 3
(or more) generations of “fundamental”
particles ) characterize by 19 constants in
• Gravity does not fit in this picture
... • surely, the genius of these giants of unification
would be lauded by their peers for decades!
I. What is String Theory?
... It accounts for about 70% of the total
energy of the Universe, and it causes the
expansion of the Universe to accelerate.
The density of this energy is 10^(-120),
when expressed in Planck units. How can
we understand this number?
Particle Physics Theory – working group
... Topics to be covered
• General philosophy: theory topics connected to the subject areas of the
other working groups should be covered within the text of those.
Theory of everything
A theory of everything (ToE) or final theory, ultimate theory, or master theory is a hypothetical single, all-encompassing, coherent theoretical framework of physics that fully explains and links together all physical aspects of the universe. Finding a ToE is one of the major unsolved problems in physics. Over the past few centuries, two theoretical frameworks have been developed that, as a whole, most closely resemble a ToE. The two theories upon which all modern physics rests are general relativity (GR) and quantum field theory (QFT). GR is a theoretical framework that only focuses on the force of gravity for understanding the universe in regions of both large-scale and high-mass: stars, galaxies, clusters of galaxies, etc. On the other hand, QFT is a theoretical framework that only focuses on three non-gravitational forces for understanding the universe in regions of both small scale and low mass: sub-atomic particles, atoms, molecules, etc. QFT successfully implemented the Standard Model and unified the interactions (so-called Grand Unified Theory) between the three non-gravitational forces: weak, strong, and electromagnetic force.Through years of research, physicists have experimentally confirmed with tremendous accuracy virtually every prediction made by these two theories when in their appropriate domains of applicability. In accordance with their findings, scientists also learned that GR and QFT, as they are currently formulated, are mutually incompatible - they cannot both be right. Since the usual domains of applicability of GR and QFT are so different, most situations require that only one of the two theories be used. As it turns out, this incompatibility between GR and QFT is only an apparent issue in regions of extremely small-scale and high-mass, such as those that exist within a black hole or during the beginning stages of the universe (i.e., the moment immediately following the Big Bang). To resolve this conflict, a theoretical framework revealing a deeper underlying reality, unifying gravity with the other three interactions, must be discovered to harmoniously integrate the realms of GR and QFT into a seamless whole: a single theory that, in principle, is capable of describing all phenomena. In pursuit of this goal, quantum gravity has recently become an area of active research.Over the past few decades, a single explanatory framework, called ""string theory"", has emerged that may turn out to be the ultimate theory of the universe. Many physicists believe that, at the beginning of the universe (up to 10−43 seconds after the Big Bang), the four fundamental forces were once a single fundamental force. Unlike most (if not all) other theories, string theory may be on its way to successfully incorporating each of the four fundamental forces into a unified whole. According to string theory, every particle in the universe, at its most microscopic level (Planck length), consists of varying combinations of vibrating strings (or strands) with preferred patterns of vibration. String theory claims that it is through these specific oscillatory patterns of strings that a particle of unique mass and force charge is created (that is to say, the electron is a type of string that vibrates one way, while the up-quark is a type of string vibrating another way, and so forth).Initially, the term theory of everything was used with an ironic connotation to refer to various overgeneralized theories. For example, a grandfather of Ijon Tichy — a character from a cycle of Stanisław Lem's science fiction stories of the 1960s — was known to work on the ""General Theory of Everything"". Physicist John Ellis claims to have introduced the term into the technical literature in an article in Nature in 1986. Over time, the term stuck in popularizations of theoretical physics research.