Strings is a series of international conferences on the topic of string theory and quantum gravity, held annually since 1988. It is a key event for the string theory community. In 2004, it gathered about 400 participants, with several more online. [1] Important topics in string theory have been introduced for the first time during these conferences.
The first conference, Strings '88 was held from May 24 to 28, 1988 at the University of Maryland, College Park. It was inspired by the International Workshop on Strings, Composite Structures and Cosmology held in the same venue a year before. [2]
The conferences were not that promising at first and some scientists suggested to stop the annual meetings, however it gained popularity in the 1990s. [3] During Strings '95. Edward Witten discussed the concept of M-theory, sparking the second superstring revolution. [4] In Strings '96, Tom Banks, Willy Fischler, Stephen Shenker, and Leonard Susskind introduced matrix theory; [5] and during Strings '98, Jeffrey A. Harvey composed a song to celebrate Juan Maldacena recent discovery of AdS/CFT correspondence. [6]
During the Strings 2000, participants proposed and selected a "Top Ten Problems in Fundamental Physics for the Next Millenium", similar to the Millennium Prize Problems in mathematics. [7] [8] The problems are:
| # | Statement | Proponents |
|---|---|---|
| 1 | Are all the (measurable) dimensionless parameters that characterize the physical universe calculable in principle or are some merely determined by historical or quantum mechanical accident and uncalculable? | David Gross |
| 2 | How can quantum gravity help explain the origin of the universe? | Edward Witten |
| 3 | What is the lifetime of the proton and how do we understand it? | Steven Gubser |
| 4 | Is Nature supersymmetric, and if so, how is supersymmetry broken? | Sergio Ferrara and Gordon L. Kane |
| 5 | Why does the universe appear to have one time and three space dimensions? | Shamit Kachru, Sunil Mukhi and Hirosi Ooguri |
| 6 | Why does the cosmological constant have the value that it has, is it zero and is it really constant? | Andrew Chambliss and Renata Kallosh |
| 7 | What are the fundamental degrees of freedom of M-theory (the theory whose low-energy limit is eleven-dimensional supergravity and which subsumes the five consistent superstring theories) and does the theory describe Nature? | Louise Dolan, Annamaria Sinkovics, and Billy & Linda Rose |
| 8 | What is the resolution of the black hole information paradox? | Tibra Ali and Samir D. Mathur |
| 9 | What physics explains the enormous disparity between the gravitational scale and the typical mass scale of the elementary particles? | Matt Strassler |
| 10 | Can we quantitatively understand quark and gluon confinement in Quantum Chromodynamics and the existence of a mass gap? | Igor Klebanov and Oyvind Tafjord |
Here is a list of Strings conferences: [9] [10]
M-theory is a theory in physics that unifies all consistent versions of superstring theory. Edward Witten first conjectured the existence of such a theory at a string theory conference at the University of Southern California in 1995. Witten's announcement initiated a flurry of research activity known as the second superstring revolution. Prior to Witten's announcement, string theorists had identified five versions of superstring theory. Although these theories initially appeared to be very different, work by many physicists showed that the theories were related in intricate and nontrivial ways. Physicists found that apparently distinct theories could be unified by mathematical transformations called S-duality and T-duality. Witten's conjecture was based in part on the existence of these dualities and in part on the relationship of the string theories to a field theory called eleven-dimensional supergravity.
In physics, string theory is a theoretical framework in which the point-like particles of particle physics are replaced by one-dimensional objects called strings. String theory describes how these strings propagate through space and interact with each other. On distance scales larger than the string scale, a string acts like a particle, with its mass, charge, and other properties determined by the vibrational state of the string. In string theory, one of the many vibrational states of the string corresponds to the graviton, a quantum mechanical particle that carries the gravitational force. Thus, string theory is a theory of quantum gravity.
Edward Witten is an American theoretical physicist known for his contributions to string theory, topological quantum field theory, and various areas of mathematics. He is a professor emeritus in the school of natural sciences at the Institute for Advanced Study in Princeton. Witten is a researcher in string theory, quantum gravity, supersymmetric quantum field theories, and other areas of mathematical physics. Witten's work has also significantly impacted pure mathematics. In 1990, he became the first physicist to be awarded a Fields Medal by the International Mathematical Union, for his mathematical insights in physics, such as his 1981 proof of the positive energy theorem in general relativity, and his interpretation of the Jones invariants of knots as Feynman integrals. He is considered the practical founder of M-theory.
Supersymmetry is a theoretical framework in physics that suggests the existence of a symmetry between particles with integer spin (bosons) and particles with half-integer spin (fermions). It proposes that for every known particle, there exists a partner particle with different spin properties. There have been multiple experiments on supersymmetry that have failed to provide evidence that it exists in nature. If evidence is found, supersymmetry could help explain certain phenomena, such as the nature of dark matter and the hierarchy problem in particle physics.
String field theory (SFT) is a formalism in string theory in which the dynamics of relativistic strings is reformulated in the language of quantum field theory. This is accomplished at the level of perturbation theory by finding a collection of vertices for joining and splitting strings, as well as string propagators, that give a Feynman diagram-like expansion for string scattering amplitudes. In most string field theories, this expansion is encoded by a classical action found by second-quantizing the free string and adding interaction terms. As is usually the case in second quantization, a classical field configuration of the second-quantized theory is given by a wave function in the original theory. In the case of string field theory, this implies that a classical configuration, usually called the string field, is given by an element of the free string Fock space.
Michio Kaku is an American physicist, science communicator, futurologist, and writer of popular-science. He is a professor of theoretical physics at the City College of New York and the CUNY Graduate Center. Kaku is the author of several books about physics and related topics and has made frequent appearances on radio, television, and film. He is also a regular contributor to his own blog, as well as other popular media outlets. For his efforts to bridge science and science fiction, he is a 2021 Sir Arthur Clarke Lifetime Achievement Awardee.
Brian Randolph Greene is an American physicist known for his research on string theory. He is a professor of physics and mathematics at Columbia University, director of its center for theoretical physics, and the chairman of the World Science Festival, which he co-founded in 2008. Greene co-discovered mirror symmetry, relating two different Calabi–Yau manifolds. He also described the flop transition, a mild form of topology change, and the conifold transition, a more severe transformation of space, showing that topology can smoothly change in string theory.
T-duality in theoretical physics is an equivalence of two physical theories, which may be either quantum field theories or string theories. In the simplest example of this relationship, one of the theories describes strings propagating in a spacetime shaped like a circle of some radius , while the other theory describes strings propagating on a spacetime shaped like a circle of radius proportional to . The idea of T-duality was first noted by Bala Sathiapalan in an obscure paper in 1987. The two T-dual theories are equivalent in the sense that all observable quantities in one description are identified with quantities in the dual description. For example, momentum in one description takes discrete values and is equal to the number of times the string winds around the circle in the dual description.
Michael James Duff FRS, FRSA is a British theoretical physicist and pioneering theorist of supergravity who is the Principal of the Faculty of Physical Sciences and Abdus Salam Chair of Theoretical Physics at Imperial College London.
The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory is a book by Brian Greene published in 1999, which introduces string and superstring theory, and provides a comprehensive though non-technical assessment of the theory and some of its shortcomings. In 2000, it won the Royal Society Prize for Science Books and was a finalist for the Pulitzer Prize for General Nonfiction. A new edition was released in 2003, with an updated preface.
In algebraic geometry and theoretical physics, mirror symmetry is a relationship between geometric objects called Calabi–Yau manifolds. The term refers to a situation where two Calabi–Yau manifolds look very different geometrically but are nevertheless equivalent when employed as extra dimensions of string theory.
Cumrun Vafa is an Iranian-American theoretical physicist and the Hollis Professor of Mathematics and Natural Philosophy at Harvard University.
Sylvester James Gates Jr., known as S. James Gates Jr. or Jim Gates, is an American theoretical physicist who works on supersymmetry, supergravity, and superstring theory. He is currently the Brown University Theoretical Physics Center Director and the Ford Foundation Professor of Physics. He also holds the Clark Leadership Chair in Science with the physics department at the University of Maryland College of Computer, Mathematical, and Natural Sciences. He is also affiliated with the University Maryland's School of Public Policy. He served on former president Barack Obama's Council of Advisors on Science and Technology.
In physics, a string is a physical entity postulated in string theory and related subjects. Unlike elementary particles, which are zero-dimensional or point-like by definition, strings are one-dimensional extended entities. Researchers often have an interest in string theories because theories in which the fundamental entities are strings rather than point particles automatically have many properties that some physicists expect to hold in a fundamental theory of physics. Most notably, a theory of strings that evolve and interact according to the rules of quantum mechanics will automatically describe quantum gravity.
Superstring theory is an attempt to explain all of the particles and fundamental forces of nature in one theory by modeling them as vibrations of tiny supersymmetric strings.
David Ian Olive ; 16 April 1937 – 7 November 2012) was a British theoretical physicist. Olive made fundamental contributions to string theory and duality theory, he is particularly known for his work on the GSO projection and Montonen–Olive duality.
Franco Selleri was an Italian theoretical physicist and professor at the Università degli Studi di Bari Aldo Moro. He received his Doctorate / Ph.D. cum laude at the Università di Bologna in 1958, and was a fellow of the Istituto Nazionale di Fisica Nucleare beginning 1959. He was a member of the New York Academy of Sciences and the Fondation Louis de Broglie, and served on the board of directors of the Italian Physical Society.
Paolo Di Vecchia is an Italian theoretical physicist who works in the field of elementary particle physics, quantum field theory and string theory.
Atish Dabholkar is an Indian theoretical physicist. He is currently the Director of the Abdus Salam International Centre for Theoretical Physics (ICTP) with the rank of Assistant Director-General, UNESCO. Prior to that, he was head of ICTP's High Energy, Cosmology and Astroparticle Physics section, and also Directeur de Recherche at the Centre National de la Recherche Scientifique (CNRS) at Sorbonne University in the "Laboratoire de Physique Théorique et Hautes Énergies" (LPTHE).
Ignatios Antoniadis is a Greek theoretical physicist, specializing in string theory and particle physics.