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Heavy Quark Effective Theory
In quantum chromodynamics, heavy quark effective theory (HQET) is an effective field theory describing the physics of heavy (that is, of mass far greater than the QCD scale) quarks. It is used in studying the properties of hadrons containing a single charm quark, charm or bottom quark, bottom quark. The effective theory was formalised in 1990 by Howard Georgi, Estia J. Eichten, Estia Eichten and Christopher T. Hill, Christopher Hill, building upon the works of Nathan Isgur and Mark B. Wise, Mark Wise, Mikhail Voloshin, Voloshin and Mikhail Shifman, Shifman,Shifman, M.A., & Voloshin, M.V. (1987). On production of D and D* mesons in B-meson decays (ITEP--64(1987)). USSR and others.Howard Georgi, Georgi, H. (1991)TASI Lectures: Heavy Quark Effective Field Theory retrieved 2016-03-01. Quantum chromodynamics (QCD) is the theory of strong interaction, strong force, through which quarks and gluons interact. HQET is the limit of QCD with the quark mass taken to infinity while its four-veloc ... [...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] |
Mikhail Voloshin
Mikhail "Misha" Voloshin (May 14, 1953, Bucharest, Romania – March 20, 2020) was a Russian and American theoretical physicist. Voloshin graduated from physics class of Moscow State School 57 in 1970. Voloshin started working at ITEP in 1976 and accordingly earned his Ph.D. in 1977. In 1983 he received a Soviet medal and an award in physics. Beginning in 1990, he taught quantum physics at the William I Fine Theoretical Physics Institute, a division of the University of Minnesota College of Science and Engineering. In 1997 elected a fellow of the American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of .... In 2001 he was awarded J.J. Sakurai Prize for Theoretical Particle Physics and in 2004 he was awarded the Alexander-von-Humboldt Award. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strange Quark
The strange quark or s quark (from its symbol, s) is the third lightest of all quarks, a type of elementary particle. Strange quarks are found in subatomic particles called hadrons. Examples of hadrons containing strange quarks include kaons (), strange D mesons (), Sigma baryons (), and other strange particles. According to the IUPAP, the symbol s is the official name, while "strange" is to be considered only as a mnemonic. The name sideways has also been used because the s quark (but also the other three remaining quarks) has an isospin, I value of 0 while the u ("up") and d ("down") quarks have values of + and − respectively. Along with the charm quark, it is part of the generation (physics), second generation of matter. It has an electric charge of elementary charge, ''e'' and a bare mass of . Like all quarks, the strange quark is an elementary particle, elementary fermion with Spin (physics), spin spin-1/2, , and experiences all four fundamental interactions: gravit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Down Quark
The down quark (symbol: d) is a type of elementary particle, and a major constituent of matter. The down quark is the second-lightest of all quarks, and combines with other quarks to form composite particles called hadrons. Down quarks are most commonly found in atomic nucleus, atomic nuclei, where it combines with up quarks to form protons and neutrons. The proton is made of one down quark with two up quarks, and the neutron is made up of two down quarks with one up quark. Because they are found in every single known atom, down quarks are present in all everyday matter that we interact with. The down quark is part of the generation (physics), first generation of matter, has an electric charge of − elementary charge, ''e'' and a Quark#Mass, bare mass of . Like all quarks, the down quark is an elementary fermion with Spin (physics), spin spin-1/2, , and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Up Quark
The up quark or u quark (symbol: u) is the lightest of all quarks, a type of elementary particle, and a significant constituent of matter. It, along with the down quark, forms the neutrons (one up quark, two down quarks) and protons (two up quarks, one down quark) of atomic nucleus, atomic nuclei. It is part of the generation (physics), first generation of matter, has an electric charge of + elementary charge, ''e'' and a Quark#Mass, bare mass of . Like all quarks, the up quark is an elementary particle, elementary fermion with Spin (physics), spin spin-1/2, , and experiences all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. The antiparticle of the up quark is the up antiquark (sometimes called ''antiup quark'' or simply ''antiup''), which differs from it only in that some of its properties, such as electric charge, charge have additive inverse, equal magnitude but opposite sign. Its existence (along with that of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Top Quark
The top quark, sometimes also referred to as the truth quark, (symbol: t) is the most massive of all observed elementary particles. It derives its mass from its coupling to the Higgs field. This coupling is very close to unity; in the Standard Model of particle physics, it is the largest (strongest) coupling at the scale of the weak interactions and above. The top quark was discovered in 1995 by the CDF and DØ experiments at Fermilab. Like all other quarks, the top quark is a fermion with spin-1/2 and participates in all four fundamental interactions: gravitation, electromagnetism, weak interactions, and strong interactions. It has an electric charge of + ''e''. It has a mass of , which is close to the rhenium atom mass. The antiparticle of the top quark is the top antiquark (symbol: , sometimes called ''antitop quark'' or simply ''antitop''), which differs from it only in that some of its properties have equal magnitude but opposite sign. The top quark interacts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-perturbative
In mathematics and physics, a non-perturbative function (mathematics), function or process is one that cannot be described by perturbation theory. An example is the function : f(x) = e^, which does not equal its own Taylor series in any neighborhood around ''x'' = 0. Every coefficient of the Taylor expansion around ''x'' = 0 is exactly zero, but the function is non-zero if ''x'' ≠ 0. In physics, such functions arise for phenomena which are impossible to understand by perturbation theory, at any finite order. In quantum field theory, 't Hooft–Polyakov monopoles, domain walls, flux tubes, and instantons are examples. A concrete, physical example is given by the Schwinger effect, whereby a strong electric field may spontaneously decay into electron-positron pairs. For not too strong fields, the rate per unit volume of this process is given by, : \Gamma = \frac \mathrm^ which cannot be expanded in a Taylor series in the electric charge e, or the electric field strength E. Her ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gluon
A gluon ( ) is a type of Massless particle, massless elementary particle that mediates the strong interaction between quarks, acting as the exchange particle for the interaction. Gluons are massless vector bosons, thereby having a Spin (physics), spin of 1. Through the strong interaction, gluons bind quarks into groups according to quantum chromodynamics, quantum chromodynamics (QCD), forming hadrons such as protons and neutrons. Gluons carry the color charge of the strong interaction, thereby participating in the strong interaction as well as mediating it. Because gluons carry the color charge, QCD is more difficult to analyze compared to quantum electrodynamics, quantum electrodynamics (QED) where the photon carries no electric charge. The term was coined by Murray Gell-Mann in 1962 for being similar to an adhesive or glue that keeps the nucleus together. Together with the quarks, these particles were referred to as Parton (particle physics), partons by Richard Feynman. P ... [...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] |
Mikhail Shifman
Mikhail "Misha" Arkadyevich Shifman (; born 4 April 1949) is a theoretical physicist (high energy physics), formerly at the Institute for Theoretical and Experimental Physics, Moscow, Ida Cohen Fine Professor of Theoretical Physics, William I. Fine Theoretical Physics Institute, University of Minnesota. Scientific contributions Shifman is known for a number of basic contributions to quantum chromodynamics, the theory of strong interactions, and to understanding of supersymmetric gauge dynamics. The most important results due to M. Shifman are diverse and include (i) the discovery of the penguin mechanism in the flavor-changing weak decays (1974); (ii) introduction of the gluon condensate and development of the SVZ sum rules relating properties of the low-lying hadronic states to the vacuum condensates (1979); (iii) introduction of the invisible (aka KSVZ) axion (1980) (iv) first exact results in supersymmetric Yang–Mills theories (NSVZ beta function, gluino condensate,198 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark B
Mark Barnes (1970 – 1 January 2016), known professionally as Mark B, was a British hip hop record producer. He was most active in the 1990s and early 2000s, associating with Blade (musician), Blade and Task Force (band), Task Force on many of his records. He was a DJ for Jazz Fudge Recordings for much of his career. Mark B first signed with Jazz Fudge in 1995. He produced some tracks for DJ Vadim's U.S.S.R. Repertoire. His first individual album was ''Underworld Connection'', released in 1997. He died in January 2016. Discography * ''Any More Questions?'' (1995) * ''Underworld Connection'' (1997) * ''Disco-Loated Beats & Sounds, Vol. 1'' (1997) * ''New Skool Dean'' (1998) * ''Hitmen for Hire'' (Mark B & Blade) (1998) * ''Nobody Relates'' (Mark B & Blade) (1998) * ''Split Personalities/From the World Lab'' (Mark B & Blade) (2000) * ''The Unknown'' (Mark B & Blade) (2000) * ''The Unknown: The New Version'' (Mark B & Blade) (2001) *0161 relief [mark b remix] (2001) *Big Tings [M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Effective Field Theory
In physics, an effective field theory is a type of approximation, or effective theory, for an underlying physical theory, such as a quantum field theory or a statistical mechanics model. An effective field theory includes the appropriate degrees of freedom (physics and chemistry), degrees of freedom to describe physical phenomena occurring at a chosen length scale or energy scale, while ignoring substructure and degrees of freedom at shorter distances (or, equivalently, at higher energies). Intuitively, one averages over the behavior of the underlying theory at shorter length scales to derive what is hoped to be a simplified model at longer length scales. Effective field theories typically work best when there is a large separation between length scale of interest and the length scale of the underlying dynamics. Effective field theories have found use in particle physics, statistical mechanics, condensed matter physics, general relativity, and hydrodynamics. They simplify calculati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
