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Bunji Sakita
was a Japanese-American theoretical physicist who made important contributions in quantum field theory, superstring theory and discovered supersymmetry in 1971. He was a Distinguished Professor of Physics at the City College of New York. Early years Bunji Sakita was born in Japan in 1930 in the Toyama prefecture. He received his bachelor's degree from Kanazawa University in 1953. He then worked with Sakata's group in Nagoya University, obtaining his master's degree in 1956. He was among a select group of Japanese students recruited by Robert Marshak to come for graduate studies to the University of Rochester. In Rochester, Sakita worked with Professor Charles Goebel and received his Ph.D in 1959. He went on to a postdoctoral position and a professorship at the University of Wisconsin–Madison. In his beginning years at Wisconsin, and during a year he spent at the Argonne National Laboratory, he developed the SU(6) symmetry of the nonrelativistic quark model generalizing Wigner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Field Theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles. QFT treats particles as excited states (also called Quantum, quanta) of their underlying quantum field (physics), fields, which are more fundamental than the particles. The equation of motion of the particle is determined by minimization of the Lagrangian, a functional of fields associated with the particle. Interactions between particles are described by interaction terms in the Lagrangian (field theory), Lagrangian involving their corresponding quantum fields. Each interaction can be visually represented by Feynman diagrams according to perturbation theory (quantum mechanics), perturbation theory in quantum mechanics. History Quantum field theory emerged from the wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual Resonance Model
In theoretical physics, a dual resonance model arose during the early investigation (1968–1973) of string theory as an S-matrix theory of the strong interaction. Overview The dual resonance model was based upon the observation that the amplitudes for the s-channel scatterings matched exactly with the amplitudes for the t-channel scatterings among mesons and also the Regge trajectory. It began with the Euler beta function model of Gabriele Veneziano in 1968 for a 4-particle amplitude which has the property that it is explicitly s–t crossing symmetric, exhibits duality between the description in terms of Regge poles or of resonances, and provides a closed-form solution to non-linear finite-energy sum rules relating s- and t- channels. The Veneziano formula was quickly generalized to an equally consistent ''N''-particle amplitude for which Yoichiro Nambu, Holger Bech Nielsen, and Leonard Susskind provided a physical interpretation in terms of an infinite number of simple harm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subatomic Particle
In physical sciences, a subatomic particle is a particle that composes an atom. According to the Standard Model of particle physics, a subatomic particle can be either a composite particle, which is composed of other particles (for example, a proton, neutron, or meson), or an elementary particle, which is not composed of other particles (for example, an electron, photon, or muon). Particle physics and nuclear physics study these particles and how they interact. Experiments show that light could behave like a stream of particles (called photons) as well as exhibiting wave-like properties. This led to the concept of wave–particle duality to reflect that quantum-scale behave like both particles and waves; they are sometimes called wavicles to reflect this. Another concept, the uncertainty principle, states that some of their properties taken together, such as their simultaneous position and momentum, cannot be measured exactly. The wave–particle duality has been shown to app ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bruno Zumino
Bruno Zumino (28 April 1923 − 21 June 2014) was an Italian theoretical physicist and faculty member at the University of California, Berkeley. He obtained his DSc degree from the University of Rome in 1945. He was renowned for his rigorous proof of the CPT theorem with Gerhart Lüders; his pioneering systematization of effective chiral Lagrangians; the discoveries, with Julius Wess, of the Wess–Zumino model, the first four-dimensional supersymmetric quantum field theory with Bose-Fermi degeneracy, and initiator of the field of supersymmetric radiative restrictions; a concise formulation of supergravity; and for his deciphering of structured flavor-chiral anomalies, codified in the Wess–Zumino–Witten model of conformal field theory. Awards * 1985 Membership in the National Academy of Sciences * 1987 Dirac Medal of the ICTP * 1988 Dannie Heineman Prize for Mathematical Physics * 1989 Max Planck Medal * 1992 Wigner Medal * 1992 Humboldt Research Award * 1999 Gian Car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Julius Wess
Julius Erich Wess (5 December 19348 August 2007) was an Austrian theoretical physicist noted as the co-inventor of the Wess–Zumino model and Wess–Zumino–Witten model in the field of supersymmetry and conformal field theory. He was also a recipient of the Max Planck medal, the Wigner medal, the Gottfried Wilhelm Leibniz Prize, the Heineman Prize, and of several honorary doctorates. Life and work Wess was born in Oberwölz Stadt, a small town in the Austrian state of Styria. He received his Ph.D. in Vienna, where he was a student of Hans Thirring. His Ph.D. examiner was acclaimed quantum mechanics physicist Erwin Schrödinger. After working at CERN in Switzerland and at the Courant Institute of New York University, United States, he became a professor at the University of Karlsruhe. In later life, Wess was professor at the Ludwig Maximilian University of Munich. After his retirement he worked at DESY in Hamburg. His doctoral students include Hermann Nicolai. Julius ... [...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] |
Fermion
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 numb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boson
In particle physics, a boson ( ) is a subatomic particle whose spin quantum number has an integer value (0,1,2 ...). Bosons form one of the two fundamental classes of subatomic particle, the other being fermions, which have odd half-integer spin (,, ...). Every observed subatomic particle is either a boson or a fermion. Bosons are named after physicist Satyendra Nath Bose. Some bosons are elementary particles and occupy a special role in particle physics unlike that of fermions, which are sometimes described as the constituents of "ordinary matter". Some elementary bosons (for example, gluons) act as force carriers, which give rise to forces between other particles, while one (the Higgs boson) gives rise to the phenomenon of mass. Other bosons, such as mesons, are composite particles made up of smaller constituents. Outside the realm of particle physics, superfluidity arises because composite bosons (bose particles), such as low temperature helium-4 atoms, follow Bose–E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riemann Surface
In mathematics, particularly in complex analysis, a Riemann surface is a connected one-dimensional complex manifold. These surfaces were first studied by and are named after Bernhard Riemann. Riemann surfaces can be thought of as deformed versions of the complex plane: locally near every point they look like patches of the complex plane, but the global topology can be quite different. For example, they can look like a sphere or a torus or several sheets glued together. The main interest in Riemann surfaces is that holomorphic functions may be defined between them. Riemann surfaces are nowadays considered the natural setting for studying the global behavior of these functions, especially multi-valued functions such as the square root and other algebraic functions, or the logarithm. Every Riemann surface is a two-dimensional real analytic manifold (i.e., a surface), but it contains more structure (specifically a complex structure) which is needed for the unambiguous definitio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Loup Gervais
Jean-Loup Gervais (born 10 September 1936 in Paris) is a French theoretical physicist. Gervais studied physics and mathematics in Paris, where he graduated in 1961 and got his Ph.D. in 1965 as a student of Claude Bouchiat and Philippe Meyer in Orsay. From 1966 to 1968 he was a post-doctoral researcher at New York University. Already since 1960 he was employed at the CNRS, from 1970 on as Maître de conférences. During 1973–1985 he was Maître de conférences at École polytechnique. From 1979 to 1983 and from 1995 to 1998 he was director of the Laboratory of Theoretical Physics of the École Normale Supérieure. He had been a guest professor at the City College of New York and also partly at University of California, Berkeley, at the Isaac Newton Institute in Cambridge (1997), at University of California, Los Angeles (UCLA) and at University of California, Santa Barbara. Gervais worked on quantum field theory, supersymmetry and string theory. In 1969, he investigated (together ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feynman Diagram
In theoretical physics, a Feynman diagram is a pictorial representation of the mathematical expressions describing the behavior and interaction of subatomic particles. The scheme is named after American physicist Richard Feynman, who introduced the diagrams in 1948. The interaction of subatomic particles can be complex and difficult to understand; Feynman diagrams give a simple visualization of what would otherwise be an arcane and abstract formula. According to David Kaiser, "Since the middle of the 20th century, theoretical physicists have increasingly turned to this tool to help them undertake critical calculations. Feynman diagrams have revolutionized nearly every aspect of theoretical physics." While the diagrams are applied primarily to quantum field theory, they can also be used in other fields, such as solid-state theory. Frank Wilczek wrote that the calculations that won him the 2004 Nobel Prize in Physics "would have been literally unthinkable without Feynman diagra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miguel Ángel Virasoro (physicist)
Miguel Ángel Virasoro (; Buenos Aires, 9 May 1940 – Buenos Aires, 23 July 2021) was an Argentine ( naturalized Italian) theoretical physicist. Virasoro worked in Argentina, Israel, the United States, and France, but he spent most of his professional career in Italy at La Sapienza University of Rome. He shared a name with his father, the philosopher Miguel Ángel Virasoro. He was known for his foundational work in string theory, the study of spin glasses, and his research in other areas of mathematical and statistical physics. The Virasoro-Shapiro amplitude,Virasoro, M. (1969). "Alternative constructions of crossing-symmetric amplitudes with Regge behavior." ''Physical Review'', 177(5), 2309–2311. the Virasoro algebra, the super Virasoro algebra, the Virasoro vertex operator algebra, the Virasoro group, the Virasoro conjecture, the Virasoro conformal block, and the Virasoro minimal model are all named after him. Biography Early life in Argentina Miguel Ángel Virasoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
