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Regge Poles
In quantum physics, Regge theory ( , ) is the study of the analytic properties of scattering as a function of angular momentum, where the angular momentum is not restricted to be an integer multiple of '' ħ'' but is allowed to take any complex value. The nonrelativistic theory was developed by Tullio Regge in 1959. Details The simplest example of Regge poles is provided by the quantum mechanical treatment of the Coulomb potential V(r) = -e^2/(4\pi\epsilon_0r) or, phrased differently, by the quantum mechanical treatment of the binding or scattering of an electron of mass m and electric charge -e off a proton of mass M and charge +e. The energy E of the binding of the electron to the proton is negative whereas for scattering the energy is positive. The formula for the binding energy is the expression :E\rightarrow E_N = - \frac = - \frac, \;\;\; m^' = \frac, where N = 1,2,3,..., h is the Planck constant, and \epsilon_0 is the permittivity of the vacuum. The principal quantum numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Physics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is the foundation of all quantum physics, which includes quantum chemistry, quantum field theory, quantum technology, and quantum information science. Quantum mechanics can describe many systems that classical physics cannot. Classical physics can describe many aspects of nature at an ordinary (macroscopic and Microscopic scale, (optical) microscopic) scale, but is not sufficient for describing them at very small submicroscopic (atomic and subatomic) scales. Classical mechanics can be derived from quantum mechanics as an approximation that is valid at ordinary scales. Quantum systems have Bound state, bound states that are Quantization (physics), quantized to Discrete mathematics, discrete values of energy, momentum, angular momentum, and ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steven Frautschi
Steven C. Frautschi (; born December 6, 1933) is an American theoretical physicist, currently professor of physics emeritus at the California Institute of Technology (Caltech). He is known principally for his contributions to the bootstrap theory of the strong interactions and for his contribution to the resolution of the infrared divergence problem in quantum electrodynamics (QED). He was named a Fellow of the American Physical Society in 2015 for "contributions to the introduction of Regge poles into particle physics, elucidation of the role of infrared photons in high energy scattering, and for seminal contributions to undergraduate physics education". Education and employment Frautschi graduated from Harvard College in 1954 and received his PhD from Stanford University in 1958, having written his dissertation on '' PC conservation in strong interactions and wide angle pair production and quantum electrodynamics at small distances'', under the supervision of Sidney Drell. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pomeron
In physics, the pomeron is a Regge trajectory — a family of particles with increasing spin — postulated in 1961 to explain the slowly rising cross section of hadronic collisions at high energies. It is named after Isaak Pomeranchuk. Overview While other trajectories lead to falling cross sections, the pomeron can lead to logarithmically rising cross sections — which, experimentally, are approximately constant ones. The identification of the pomeron and the prediction of its properties was a major success of the Regge theory of strong interaction phenomenology. In later years, a BFKL pomeron was derived in further kinematic regimes from perturbative calculations in QCD, but its relationship to the pomeron seen in soft high energy scattering is still not fully understood. One consequence of the pomeron hypothesis is that the cross sections of proton–proton and proton–antiproton scattering should be equal at high enough energies. This was demonstrated by the Soviet ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasinormal Mode
Quasinormal modes (QNM) are the modes of energy dissipation of a perturbed object or field, ''i.e.'' they describe perturbations of a field that decay in time. Example A familiar example is the perturbation (gentle tap) of a wine glass with a knife: the glass begins to ring, it rings with a set, or superposition, of its natural frequencies — its modes of sonic energy dissipation. One could call these modes '' normal'' if the glass went on ringing forever. Here the amplitude of oscillation decays in time, so we call its modes ''quasi-normal''. To a high degree of accuracy, quasinormal ringing can be approximated by :\psi(t) \approx e^\cos\omega^t where \psi\left(t\right) is the amplitude of oscillation, \omega^ is the frequency, and \omega^ is the decay rate. The quasinormal frequency is described by two numbers, :\omega = \left(\omega^ , \omega^\right) or, more compactly :\psi\left(t\right) \approx \operatorname(e^) :\omega =\omega^ + i\omega^ Here, \mathbf is what is com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quark–gluon Plasma
Quark–gluon plasma (QGP or quark soup) is an interacting localized assembly of quarks and gluons at Thermodynamic equilibrium#Local and global equilibrium, thermal (local kinetic) and (close to) chemical (abundance) equilibrium. The word ''plasma'' signals that free color charges are allowed. In a 1987 summary, Léon Van Hove pointed out the equivalence of the three terms: quark gluon plasma, quark matter and a new state of matter. Since the temperature is above the Hagedorn temperature—and thus above the scale of light u,d-quark mass—the pressure exhibits the relativistic Stefan–Boltzmann law, Stefan–Boltzmann format governed by temperature to the fourth power ( T^) and many practically massless quark and gluon constituents. It can be said that QGP emerges to be the new phase of strongly interacting matter which manifests its physical properties in terms of nearly free dynamics of practically massless gluons and quarks. Both quarks and gluons must be present in conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Chromodynamics
In theoretical physics, quantum chromodynamics (QCD) is the study of the strong interaction between quarks mediated by gluons. Quarks are fundamental particles that make up composite hadrons such as the proton, neutron and pion. QCD is a type of quantum field theory called a non-abelian gauge theory, with symmetry group special unitary group, SU(3). The QCD analog of electric charge is a property called ''color''. Gluons are the force carriers of the theory, just as photons are for the electromagnetic force in quantum electrodynamics. The theory is an important part of the Standard Model of particle physics. A large body of Quantum chromodynamics#Experimental tests, experimental evidence for QCD has been gathered over the years. QCD exhibits three salient properties: * Color confinement. Due to the force between two color charges remaining constant as they are separated, the energy grows until a quark–antiquark pair is mass–energy equivalence, spontaneously produced, turning ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strong Interaction
In nuclear physics and particle physics, the strong interaction, also called the strong force or strong nuclear force, is one of the four known fundamental interaction, fundamental interactions. It confines Quark, quarks into proton, protons, neutron, neutrons, and other hadron particles, and also binds neutrons and protons to create atomic nuclei, where it is called the nuclear force. Most of the mass–energy equivalence, mass of a proton or neutron is the result of the strong interaction energy; the individual quarks provide only about 1% of the mass of a proton. At the range of 10−15 m (1 femtometer, slightly more than the radius of a nucleon), the strong force is approximately 100 times as strong as electromagnetism, 106 times as strong as the weak interaction, and 1038 times as strong as Gravity, gravitation. In the context of atomic nuclei, the force binds protons and neutrons together to form a nucleus and is called the nuclear force (or ''residual strong force'' ... [...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] |
Gabriele Veneziano
Gabriele Veneziano ( ; ; born 7 September 1942) is an Italian theoretical physicist widely considered the father of string theory. He has conducted most of his scientific activities at CERN in Geneva, Switzerland, and held the Chair of Elementary Particles, Gravitation and Cosmology at the Collège de France in Paris from 2004 to 2013, until the age of retirement there. Life Gabriele Veneziano was born in Florence. In 1965, he earned his Laurea in Theoretical Physics from the University of Florence under the direction of . He pursued his doctoral studies at the Weizmann Institute of Science in Rehovot, Israel and obtained his PhD in 1967 under the supervision of Hector Rubinstein. During his stay in Israel, he collaborated, among others, with Marco Ademollo (a professor in Florence) and Miguel Virasoro (an Argentinian physicist who later became a professor in Italy). During his years at MIT, he collaborated with many colleagues, primarily with Sergio Fubini (an MIT professor, la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Horn (Israeli Physicist)
David Horn (; born 10 September 1937) is a Professor (Emeritus) of Physics in the School of Physics and Astronomy at Tel Aviv University (TAU), Israel. He has served as Vice- Rector of TAU, Chairman of the School of Physics and Astronomy and as Dean of the Faculty of Exact Sciences in TAU. He is a fellow of the American Physical Society, nominated for "contributions to theoretical particle physics, including the seminal work on finite energy sum rules, research of the phenomenology of hadronic processes, and investigation of Hamiltonian lattice theories". Early life and education David Horn was born and educated in Haifa. He graduated from the Reali School in 1955. He began his academic studies in Physics at the Technion in Haifa in 1957, and received his B.Sc. (Summa Cum Laude) in 1961, and M.Sc. in 1962. He continued his Ph.D. studies at the Hebrew University of Jerusalem until 1965. His thesis on "Some Aspects of the Structure of Weak Interactions" was supervised by Prof. Yuv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-matrix Theory
''S''-matrix theory was a proposal for replacing local quantum field theory as the basic principle of elementary particle physics. It avoided the notion of space and time by replacing it with abstract mathematical properties of the ''S''-matrix. In ''S''-matrix theory, the ''S''-matrix relates the infinite past to the infinite future in one step, without being decomposable into intermediate steps corresponding to time-slices. This program was very influential in the 1960s, because it was a plausible substitute for quantum field theory, which was plagued with the zero interaction phenomenon at strong coupling. Applied to the strong interaction, it led to the development of string theory. ''S''-matrix theory was largely abandoned by physicists in the 1970s, as quantum chromodynamics was recognized to solve the problems of strong interactions within the framework of field theory. But in the guise of string theory, ''S''-matrix theory is still a popular approach to the problem of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantitative Perturbation Theory
Quantitative may refer to: * Quantitative research, scientific investigation of quantitative properties * Quantitative analysis (other) * Quantitative verse, a metrical system in poetry * Statistics, also known as quantitative analysis * Numerical data, also known as quantitative data * Quantification (science) In mathematics and empirical science, quantification (or quantitation) is the act of counting and measuring that maps human sense observations and experiences into quantity, quantities. Quantification in this sense is fundamental to the scientific ... See also * Qualitative {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
