Klaus Fredenhagen
Klaus Fredenhagen (born 1 December 1947) is a German theoretical physicist who works on the mathematical foundations of quantum field theory. Biography Klaus Fredenhagen was born on 1 December 1947 in Celle, a German city in Lower Saxony. He graduated in 1976 from the University of Hamburg under the supervision of Gert Roepstorff and Rudolf Haag. In 1985 he became a privatdozent and in 1990 a full professor at the second theory institute of the Hamburg University. Since 2013 he has been a professor emeritus and has continued to be active in research. Scientific career His research interests are algebraic quantum field theory and quantum field theory in curved spacetime. In 1981 he proved the existence of antiparticles in massive quantum field theories without using the CPT-invariance. In 1990 he and Rudolf Haag made important contributions to the understanding of the Hawking radiation of black holes on a rigorous mathematical footing. In 1994, together with Sergio Dopliche ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Roberto Longo (mathematician)
Roberto Longo (born 9 May 1953) is an Italian mathematician, specializing in operator algebras and quantum field theory. Education and career Roberto Longo graduated in Mathematics at the Sapienza University of Rome in 1975 under the supervision of the mathematical physicist Sergio Doplicher. From 1975 to 1977 Longo was a predoctoral fellow of the Consiglio Nazionale delle Ricerche and later assistant professor at the Sapienza University of Rome, where he became an associate professor in 1980. In 1987 he was nominated full professor of functional analysis at the University of Rome Tor Vergata and since 2010 he is the director of the Center for Mathematics and Theoretical Physics in Rome. Between 1978 and 1979 he was visiting scholar at the University of Pennsylvania and the University of California, Berkeley. He has been a visiting professor in numerous research centers, including the CNRS in Marseille, the Mathematical Sciences Research Institute in Berkeley, California, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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CPT Symmetry
Charge, parity, and time reversal symmetry is a fundamental symmetry of physical laws under the simultaneous transformations of charge conjugation (C), parity transformation (P), and time reversal (T). CPT is the only combination of C, P, and T that is observed to be an exact symmetry of nature at the fundamental level. The CPT theorem says that CPT symmetry holds for all physical phenomena, or more precisely, that any Lorentz invariant local quantum field theory with a Hermitian Hamiltonian must have CPT symmetry. History The CPT theorem appeared for the first time, implicitly, in the work of Julian Schwinger in 1951 to prove the connection between spin and statistics. In 1954, Gerhart Lüders and Wolfgang Pauli derived more explicit proofs, so this theorem is sometimes known as the Lüders–Pauli theorem. At about the same time, and independently, this theorem was also proved by John Stewart Bell. These proofs are based on the principle of Lorentz invariance and the princ ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Microlocal Analysis
In mathematical analysis, microlocal analysis comprises techniques developed from the 1950s onwards based on Fourier transforms related to the study of variable-coefficients-linear and nonlinear partial differential equations. This includes generalized functions, pseudo-differential operators, wave front sets, Fourier integral operators, oscillatory integral operators, and paradifferential operators. The term ''microlocal'' implies localisation not only with respect to location in the space, but also with respect to cotangent space directions at a given point. This gains in importance on manifolds of dimension greater than one. See also *Algebraic analysis *Microfunction External linkslecture notes by Richard Melrose Microlocal analysis, Fourier analysis Generalized functions {{Mathanalysis-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Local Quantum Physics
Algebraic quantum field theory (AQFT) is an application to local quantum physics of C*-algebra theory. Also referred to as the Haag–Kastler axiomatic framework for quantum field theory, because it was introduced by . The axioms are stated in terms of an algebra given for every open set in Minkowski space, and mappings between those. Haag–Kastler axioms Let \mathcal be the set of all open and bounded subsets of Minkowski space. An algebraic quantum field theory is defined via a net \_ of von Neumann algebras \mathcal(O) on a common Hilbert space \mathcal satisfying the following axioms: * ''Isotony'': O_1 \subset O_2 implies \mathcal(O_1) \subset \mathcal(O_2). * ''Causality'': If O_1 is space-like separated from O_2, then mathcal(O_1),\mathcal(O_2)0. * ''Poincaré covariance'': A strongly continuous unitary representation U(\mathcal) of the Poincaré group \mathcal on \mathcal exists such that \mathcal(gO) = U(g) \mathcal(O) U(g)^*, g \in \mathcal. * ''Spectrum condition'': ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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University Of Leipzig
Leipzig University (german: Universität Leipzig), in Leipzig in Saxony, Germany, is one of the world's oldest universities and the second-oldest university (by consecutive years of existence) in Germany. The university was founded on 2 December 1409 by Frederick I, Elector of Saxony and his brother William II, Margrave of Meissen, and originally comprised the four scholastic faculties. Since its inception, the university has engaged in teaching and research for over 600 years without interruption. Famous alumni include Gottfried Wilhelm von Leibniz, Johann Wolfgang von Goethe, Leopold von Ranke, Friedrich Nietzsche, Robert Schumann, Richard Wagner, Tycho Brahe, Georgius Agricola, Angela Merkel and ten Nobel laureates associated with the university. History Founding and development until 1900 The university was modelled on the University of Prague, from which the German-speaking faculty members withdrew to Leipzig after the Jan Hus crisis and the Decree of Kutná H ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Göttingen Academy Of Sciences
Göttingen (, , ; nds, Chöttingen) is a university city in Lower Saxony, central Germany, the capital of the eponymous district. The River Leine runs through it. At the end of 2019, the population was 118,911. General information The origins of Göttingen lay in a village called ''Gutingi, ''first mentioned in a document in 953 AD. The city was founded northwest of this village, between 1150 and 1200 AD, and adopted its name. In medieval times the city was a member of the Hanseatic League and hence a wealthy town. Today, Göttingen is famous for its old university (''Georgia Augusta'', or "Georg-August-Universität"), which was founded in 1734 (first classes in 1737) and became the most visited university of Europe. In 1837, seven professors protested against the absolute sovereignty of the kings of Hanover; they lost their positions, but became known as the "Göttingen Seven". Its alumni include some well-known historical figures: the Brothers Grimm, Heinrich Ewald, ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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C*-algebra
In mathematics, specifically in functional analysis, a C∗-algebra (pronounced "C-star") is a Banach algebra together with an involution satisfying the properties of the adjoint. A particular case is that of a complex algebra ''A'' of continuous linear operators on a complex Hilbert space with two additional properties: * ''A'' is a topologically closed set in the norm topology of operators. * ''A'' is closed under the operation of taking adjoints of operators. Another important class of non-Hilbert C*-algebras includes the algebra C_0(X) of complex-valued continuous functions on ''X'' that vanish at infinity, where ''X'' is a locally compact Hausdorff space. C*-algebras were first considered primarily for their use in quantum mechanics to model algebras of physical observables. This line of research began with Werner Heisenberg's matrix mechanics and in a more mathematically developed form with Pascual Jordan around 1933. Subsequently, John von Neumann attempted to establi ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Detlev Buchholz
Detlev Buchholz (born 31 May 1944) is a German theoretical physicist. He investigates quantum field theory, especially in the axiomatic framework of algebraic quantum field theory. Biography Buchholz studied physics in Hannover and Hamburg where he acquired his Diplom in 1968. After graduation, he continued his studies in Physics in Hamburg. In 1970–1971 he was at the University of Pennsylvania. After receiving his PhD in 1973 under Rudolf Haag he worked at the University of Hamburg and was in 1974–1975 at CERN. From 1975 to 1978 he worked as a research assistant in Hamburg, where he got his habilitation in 1977. In 1978–1979 he had a Max Kade grant at the University of California, Berkeley. In 1979 he was a professor in Hamburg and changed to the University of Göttingen in 1997. He retired in 2010 as professor emeritus. Buchholz made contributions to relativistic quantum physics and quantum field theory, especially in the area of algebraic quantum field theory. Usin ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Microlocal Analysis
In mathematical analysis, microlocal analysis comprises techniques developed from the 1950s onwards based on Fourier transforms related to the study of variable-coefficients-linear and nonlinear partial differential equations. This includes generalized functions, pseudo-differential operators, wave front sets, Fourier integral operators, oscillatory integral operators, and paradifferential operators. The term ''microlocal'' implies localisation not only with respect to location in the space, but also with respect to cotangent space directions at a given point. This gains in importance on manifolds of dimension greater than one. See also *Algebraic analysis *Microfunction External linkslecture notes by Richard Melrose Microlocal analysis, Fourier analysis Generalized functions {{Mathanalysis-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Vladimir Jurko Glaser
Vladimir Jurko Glaser (21 April 1924 – 22 January 1984) was a Croatian theoretical physicist working on quantum field theory and the canonization of the analytic S-matrix. Biography Glaser was born in Gorizia, Italy. His father, Vladimir Glaser, was a prominent Slovene lawyer and minority rights activist. His mother, Ana née Besednjak, was the sister of the politician Engelbert Besednjak. His paternal aunt Eleonora (Lola) was married to the famous neurologist Constantin von Economo. The family fled to Yugoslavia in 1929, first to Maribor, then to Belgrade, Odžaci and finally to Zagreb in 1941. He graduated physics from the University of Zagreb in 1949 and later was attending seminar of Werner Heisenberg (1951-52) at Göttingen. Based on work carried out in Göttingen under Heisenberg he received a doctorate degree from the University of Zagreb. Being a part of Heisenberg's group at Göttingen he later worked with many famous physicists such as Harry Lehmann, Wolfhart Zimmerman ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Quantum Gravity
Quantum gravity (QG) is a field of theoretical physics that seeks to describe gravity according to the principles of quantum mechanics; it deals with environments in which neither gravitational nor quantum effects can be ignored, such as in the vicinity of black holes or similar compact astrophysical objects, such as neutron stars. Three of the four fundamental forces of physics are described within the framework of quantum mechanics and quantum field theory. The current understanding of the fourth force, gravity, is based on Albert Einstein's general theory of relativity, which is formulated within the entirely different framework of classical physics. However, that description is incomplete: describing the gravitational field of a black hole in the general theory of relativity leads physical quantities, such as the spacetime curvature, to diverge at the center of the black hole. This signals the breakdown of the general theory of relativity and the need for a theory that goes b ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |