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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 Wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Field Theory
In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines Field theory (physics), field theory and the principle of relativity with ideas behind 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. The current standard model of particle physics is based on QFT. History Quantum field theory emerged from the work of generations of theoretical physicists spanning much of the 20th century. Its development began in the 1920s with the description of interactions between light and electrons, culminating in the first quantum field theory—quantum electrodynamics. A major theoretical obstacle soon followed with the appearance and persistence of various infinities in perturbative calculations, a problem only resolved in the 1950s with the invention of the renormalization procedure. A second major barrier came with QFT's apparent inabili ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subatomic Particle
In physics, a subatomic particle is a particle smaller than 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 baryon, like a proton or a neutron, composed of three quarks; or a meson, composed of two quarks), or an elementary particle, which is not composed of other particles (for example, quarks; or electrons, muons, and tau particles, which are called leptons). Particle physics and nuclear physics study these particles and how they interact. Most force-carrying particles like photons or gluons are called bosons and, although they have quanta of energy, do not have rest mass or discrete diameters (other than pure energy wavelength) and are unlike the former particles that have rest mass and cannot overlap or combine which are called fermions. The W and Z bosons, however, are an exception to this rule and have relatively large rest masses at approxim ... [...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 flavour-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 G ... [...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.In 1957 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 ... [...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 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. 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 condensed matter ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermion
In particle physics, a fermion is a subatomic particle that follows Fermi–Dirac statistics. Fermions have a half-integer spin (spin 1/2, spin , Spin (physics)#Higher spins, spin , etc.) and obey the Pauli exclusion principle. These particles include all quarks and leptons and all composite particles made of an even and odd, odd number of these, such as all baryons and many atoms and atomic nucleus, 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 Theory of relativity, relativistic quantum field theory, particles with integer Spin (physics), 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 referr ... [...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 half odd-integer spin (1/2, 3/2, 5/2, ...). Every observed subatomic particle is either a boson or a fermion. Paul Dirac coined the name ''boson'' to commemorate the contribution of Satyendra Nath Bose, an Indian physicist. Some bosons are elementary particles occupying a special role in particle physics, distinct from the role of fermions (which are sometimes described as the constituents of "ordinary matter"). Certain elementary bosons (e.g. gluons) act as force carriers, which give rise to forces between other particles, while one (the Higgs boson) contributes to the phenomenon of mass. Other bosons, such as mesons, are composite particles made up of smaller constituents. Outside the realm of particle physics, multiple identical composite bosons ... [...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. Examples of Riemann surfaces include Graph of a function, graphs of Multivalued function, multivalued functions such as √''z'' or log(''z''), e.g. the subset of pairs with . Every Riemann surface is a Surface (topology), surface: a two-dimensional real manifold, but it contains more structure (specifically a Complex Manifold, complex structure). Conversely, a two-dimensional real manifold can be turned into a Riemann surface (usually in several inequivalent ways) if and only if it is orientable and Metrizabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Loup Gervais
Jean-Loup Gervais (10 September 1936 – 1 February 2020) was 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 (t ... [...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 calculation of probability amplitudes in theoretical particle physics requires the use of large, complicated integrals over a large number of variables. Feynman diagrams instead represent these integrals graphically. 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 apply primarily to quantum field theory, they can be used in other areas of physics, such as solid-state theory. Frank Wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miguel Ángel Virasoro (physicist)
Miguel Ángel Virasoro (;9 May 1940 – 23 July 2021) was an Argentine (naturalized Italian) mathematician and 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 was born i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
