Ryan Milton Rohm (born 22 December 1957, Gastonia, North Carolina) is an American string theorist. He is one of four physicists known as the Princeton string quartet, [1] and is responsible for the development of heterotic string theory along with David Gross, Jeffrey A. Harvey and Emil Martinec, [1] [2] [3] [4] [5] the other members of the Princeton String Quartet.
Rohm studied physics and mathematics at North Carolina State University (NCSU) with a bachelor's degree in 1980 and received a Ph.D. in physics from Princeton University in 1985. He was a postdoc from 1985 to 1988 at Caltech. From 1988 to 1995 he was an assistant professor at Boston University. In 1997 he earned a master's degree in computer science at NCSU. Since 1998 he has worked on experimental neutrino physics in the KamLAND experiment and at the Triangle Universities Nuclear Laboratory (TUNL). Since 1997 he has also been an adjunct professor at the University of North Carolina at Chapel Hill. [6]
The interacting boson model (IBM) is a model in nuclear physics in which nucleons (protons or neutrons) pair up, essentially acting as a single particle with boson properties, with integral spin of either 2 (d-boson) or 0 (s-boson). They correspond to a quintuplet and singlet, i.e. 6 states.
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.
In string theory, a heterotic string is a closed string (or loop) which is a hybrid ('heterotic') of a superstring and a bosonic string. There are two kinds of heterotic superstring theories, the heterotic SO(32) and the heterotic E8 × E8, abbreviated to HO and HE. Apart from that there exist seven more heterotic string theories which are not supersymmetric and hence are only of secondary importance in most applications. Heterotic string theory was first developed in 1985 by David Gross, Jeffrey Harvey, Emil Martinec, and Ryan Rohm (the so-called "Princeton string quartet"), in one of the key papers that fueled the first superstring revolution.
Jeffrey A. Harvey is an American string theorist at the University of Chicago.
Malcolm John Perry is a British theoretical physicist and emeritus professor of theoretical physics at University of Cambridge and professor of theoretical physics at Queen Mary University of London. His research mainly concerns quantum gravity, black holes, general relativity, and supergravity.
Montonen–Olive duality or electric–magnetic duality is the oldest known example of strong–weak duality or S-duality according to current terminology. It generalizes the electro-magnetic symmetry of Maxwell's equations by stating that magnetic monopoles, which are usually viewed as emergent quasiparticles that are "composite", can in fact be viewed as "elementary" quantized particles with electrons playing the reverse role of "composite" topological solitons; the viewpoints are equivalent and the situation dependent on the duality. It was later proven to hold true when dealing with a N = 4 supersymmetric Yang–Mills theory. It is named after Finnish physicist Claus Montonen and British physicist David Olive after they proposed the idea in their academic paper Magnetic monopoles as gauge particles? where they state:
There should be two "dual equivalent" field formulations of the same theory in which electric (Noether) and magnetic (topological) quantum numbers exchange roles.
Emil John Martinec is an American string theorist, a physics professor at the Enrico Fermi Institute at the University of Chicago, and director of the Kadanoff Center for Theoretical Physics. He was part of a group at Princeton University that developed heterotic string theory in 1985.
Tamiaki Yoneya is a Japanese physicist.
In theoretical physics, boundary conformal field theory (BCFT) is a conformal field theory defined on a spacetime with a boundary. Different kinds of boundary conditions for the fields may be imposed on the fundamental fields; for example, Neumann boundary condition or Dirichlet boundary condition is acceptable for free bosonic fields. BCFT was developed by John Cardy.
Édouard Brézin is a French theoretical physicist. He is professor at Université Paris 6, working at the laboratory for theoretical physics (LPT) of the École Normale Supérieure since 1986.
Igor R. Klebanov is an American theoretical physicist. Since 1989, he has been a faculty member at Princeton University, where he is currently a Eugene Higgins Professor of Physics and the director of the Princeton Center for Theoretical Science. In 2016, he was elected to the National Academy of Sciences. Since 2022, he is the director of the Simons Collaboration on Confinement and QCD Strings.
In mathematical physics, a super Virasoro algebra is an extension of the Virasoro algebra to a Lie superalgebra. There are two extensions with particular importance in superstring theory: the Ramond algebra and the Neveu–Schwarz algebra. Both algebras have N = 1 supersymmetry and an even part given by the Virasoro algebra. They describe the symmetries of a superstring in two different sectors, called the Ramond sector and the Neveu–Schwarz sector.
In superstring theory, a picture is a choice of Fock space or, equivalently, a choice of ground state that defines a representation of the theory's state space. Each picture is denoted by a number, such as the 0 picture or −1 picture, and picture-changing operators transform from one representation to another. The use of these operators in BRST quantization is credited to Daniel Friedan, Emil Martinec, and Stephen Shenker in the 1980s, though it has a predecessor in the dual models of the early 1970s.
The history of string theory spans several decades of intense research including two superstring revolutions. Through the combined efforts of many researchers, string theory has developed into a broad and varied subject with connections to quantum gravity, particle and condensed matter physics, cosmology, and pure mathematics.
The non-critical string theory describes the relativistic string without enforcing the critical dimension. Although this allows the construction of a string theory in 4 spacetime dimensions, such a theory usually does not describe a Lorentz invariant background. However, there are recent developments which make possible Lorentz invariant quantization of string theory in 4-dimensional Minkowski space-time.
Xiao-Gang Wen is a Chinese-American physicist. He is a Cecil and Ida Green Professor of Physics at the Massachusetts Institute of Technology and Distinguished Visiting Research Chair at the Perimeter Institute for Theoretical Physics. His expertise is in condensed matter theory in strongly correlated electronic systems. In Oct. 2016, he was awarded the Oliver E. Buckley Condensed Matter Prize.
Christof Wetterich is a German theoretical physicist. He is known for researches in quintessence, Wetterich equation for Functional renormalization, Asymptotic safety in quantum gravity.
Paul Stephen Aspinwall is a British theoretical physicist and mathematician, who works on string theory and also algebraic geometry.
Michael Dine is an American theoretical physicist, specializing in elementary particle physics, supersymmetry, string theory, and physics beyond the Standard Model.
Costas Christou Kounnas was a Cypriot theoretical physicist, known for his research on string theory, supersymmetry, supergravity, GUTs, and quantum chromodynamics.