|
GS Formalism
Green–Schwarz (GS) formalism (named after Michael Green and John H. Schwarz) is an attempt to introduce fermions in string theory. The theory is equivalent to RNS formalism which has been GSO projected. This theory is very hard to quantize, being straightforward to quantize only in light cone gauge. A covariant quantization of spinning string, maintaining space-time supersymmetry manifest, is possible in a formalism inspired on the GS formalism, known as pure spinor formalism.N. Bekovits, "Super-Poincaré covariant quantization of the superstring." Journal of High Energy Physics 2000.04 (2000): 018. See also * Supersymmetry *RNS formalism Ramond–Neveu–Schwarz (RNS) formalism (named after Pierre Ramond, John H. Schwarz, and André Neveu) was an early attempt to introduce fermions through the means of supersymmetry into string theory. In this theory, worldsheet embedded in spac ... Notes category:string theory {{string-theory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Green (physicist)
Michael Boris Green (born 22 May 1946) is a British physicist and a pioneer of string theory. He is Professor of Theoretical Physics in the School of Physics and Astronomy at Queen Mary University of London, emeritus professor in the Department of Applied Mathematics and Theoretical Physics and a Fellow of Clare Hall, Cambridge. He was Lucasian Professor of Mathematics from 2009 to 2015. Education and background Green was born the son of Genia Green and Absalom Green. He attended William Ellis School in London and Churchill College, Cambridge where he graduated with a Bachelor of Arts with first class honours in theoretical physics (1967) and a PhD in elementary particle theory (1970). Career Following his PhD, Green did postdoctoral research at Princeton University (1970–72), Cambridge and the University of Oxford. Between 1978 and 1993 he was a Lecturer and Professor at Queen Mary College, University of London, and in July 1993 he was appointed John Humphrey Plummer Profes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John H
John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second Epistle of John, often shortened to 2 John * Third Epistle of John, often shortened to 3 John People * John the Baptist (died c. AD 30), regarded as a prophet and the forerunner of Jesus Christ * John the Apostle (lived c. AD 30), one of the twelve apostles of Jesus * John the Evangelist, assigned author of the Fourth Gospel, once identified with the Apostle * John of Patmos, also known as John the Divine or John the Revelator, the author of the Book of Revelation, once identified with the Apostle * John the Presbyter, a figure either identified with or distinguished from the Apostle, the Evangelist and John of Patmos Other people with the given name Religious figures * John, father of Andrew the Apostle and Saint Peter * Pope Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermions
In particle physics, a fermion is a particle that follows Fermi–Dirac statistics. Generally, it has a half-odd-integer spin: spin , spin , etc. In addition, these particles obey the Pauli exclusion principle. Fermions include all quarks and leptons and all composite particles made of an odd number of these, such as all baryons and many atoms and nuclei. Fermions differ from bosons, which obey Bose–Einstein statistics. Some fermions are elementary particles (such as electrons), and some are composite particles (such as protons). For example, according to the spin-statistics theorem in relativistic quantum field theory, particles with integer spin are bosons. In contrast, particles with half-integer spin are fermions. In addition to the spin characteristic, fermions have another specific property: they possess conserved baryon or lepton quantum numbers. Therefore, what is usually referred to as the spin-statistics relation is, in fact, a spin statistics-quantum number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
String Theory
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 looks just like an ordinary 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. String theory is a broad and varied subject that attempts to address a number of deep questions of fundamental physics. String theory has contributed a number of advances to mathematical physics, which have been applied to a variety of problems in black hole physics, early universe cosmology, nuclear physics, and conde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNS Formalism
Ramond–Neveu–Schwarz (RNS) formalism (named after Pierre Ramond, John H. Schwarz, and André Neveu) was an early attempt to introduce fermions through the means of supersymmetry into string theory. In this theory, worldsheet embedded in spacetime is regarded as a bosonic field and the fermionic fields are regarded as the vectors of spacetime. The theory can map out tachyon through GSO projection. Also, RNS formalism is equivalent to GS formalism which has spacetime supersymmetry but without worldsheet supersymmetry. See also * GS formalism *GSO projection *Kalb–Ramond field In theoretical physics in general and string theory in particular, the Kalb–Ramond field (named after Michael Kalb and Pierre Ramond), also known as the Kalb–Ramond ''B''-field or Kalb–Ramond NS–NS ''B''-field, is a quantum field that tran ... References References * Thomas Mohaupt (2002)"Introduction to String Theory" String theory {{string-theory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GSO Projection
The GSO projection (named after Ferdinando Gliozzi, Joël Scherk, and David I. Olive) F. Gliozzi, J. Scherk and D. I. Olive, "Supersymmetry, Supergravity Theories and the Dual Spinor Model", ''Nucl. Phys. B'' 122 (1977), 253. is an ingredient used in constructing a consistent model in superstring theory. The projection is a selection of a subset of possible vertex operators in the worldsheet conformal field theory (CFT)—usually those with specific worldsheet fermion number and periodicity conditions. Such a projection is necessary to obtain a consistent worldsheet CFT. For the projection to be consistent, the set ''A'' of operators retained by the projection must satisfy: * Closure — The operator product expansion (OPE) of any two operators in ''A'' contains only operators which are in ''A''. * Mutual locality — There are no branch cuts in the OPE of any two operators in the set ''A''. * Modular invariance — The partition function on the two-torus of the theory cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Cone Gauge
In theoretical physics, light cone gauge is an approach to remove the ambiguities arising from a gauge symmetry. While the term refers to several situations, a null component of a field ''A'' is set to zero (or a simple function of other variables) in all cases.''QCD calculations in the light-cone gauge'' Nuclear Physics B - Volume 165, Issue 2, 24 March 1980, Pages 237–268 by D.J. Pritchard, W.J. Stirlin/ref> The advantage of light-cone gauge is that fields, e.g. gluons in the QCD case, are transverse. Consequently, all ghosts and other unphysical degrees of freedom are eliminated. The disadvantage is that some symmetries such as Lorentz symmetry become obscured (they become non-manifest, i.e. hard to prove). Gauge theory In gauge theory, light-cone gauge refers to the condition A^+=0 where :A^+ (x^0,x^1,x^2,x^3) = A^0 (x^0,x^1,x^2,x^3) +A^3 (x^0,x^1,x^2,x^3) It is a method to get rid of the redundancies implied by Yang–Mills symmetry. String theory In string theory, lig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersymmetry
In a supersymmetric theory the equations for force and the equations for matter are identical. In theoretical and mathematical physics, any theory with this property has the principle of supersymmetry (SUSY). Dozens of supersymmetric theories exist. Supersymmetry is a spacetime symmetry between two basic classes of particles: bosons, which have an integer-valued spin and follow Bose–Einstein statistics, and fermions, which have a half-integer-valued spin and follow Fermi–Dirac statistics. In supersymmetry, each particle from one class would have an associated particle in the other, known as its superpartner, the spin of which differs by a half-integer. For example, if the electron exists in a supersymmetric theory, then there would be a particle called a ''"selectron"'' (superpartner electron), a bosonic partner of the electron. In the simplest supersymmetry theories, with perfectly " unbroken" supersymmetry, each pair of superpartners would share the same mass and intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pure Spinor
In the domain of mathematics known as representation theory, pure spinors (or simple spinors) are spinors that are annihilated under the Clifford action by a maximal isotropic subspace of the space V of vectors with respect to the scalar product determining the Clifford algebra. They were introduced by Élie Cartan in the 1930s to classify complex structures. Pure spinors were a key ingredient in the study of spin geometry and twistor theory, introduced by Roger Penrose in the 1960s. Definition Consider a complex vector space V with either even complex dimension 2n or odd complex dimension 2n+1 and a nondegenerate complex scalar product Q , with values Q(u,v) on pairs of vectors (u, v) . The Clifford algebra Cl(V, Q) is the quotient of the full tensor algebra on V by the ideal generated by the relations :u\otimes v + v \otimes u = Q(u,v), \quad \forall \ u, v \in V. Spinors are modules of the Clifford algebra, and so in particular there is an action ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supersymmetry
In a supersymmetric theory the equations for force and the equations for matter are identical. In theoretical and mathematical physics, any theory with this property has the principle of supersymmetry (SUSY). Dozens of supersymmetric theories exist. Supersymmetry is a spacetime symmetry between two basic classes of particles: bosons, which have an integer-valued spin and follow Bose–Einstein statistics, and fermions, which have a half-integer-valued spin and follow Fermi–Dirac statistics. In supersymmetry, each particle from one class would have an associated particle in the other, known as its superpartner, the spin of which differs by a half-integer. For example, if the electron exists in a supersymmetric theory, then there would be a particle called a ''"selectron"'' (superpartner electron), a bosonic partner of the electron. In the simplest supersymmetry theories, with perfectly " unbroken" supersymmetry, each pair of superpartners would share the same mass and intern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
