Unreferenced date December 2009 In physics , a pseudoscalar is a quantity that behaves like a scalar physics scalar , except that it changes sign under a Parity physics parity inversion such as improper rotation s while a true scalar does not. The prototypical example of a pseudoscalar is the scalar triple product . A pseudoscalar, when multiplied by an ordinary vector space vector , becomes a pseudovector or axial vector a similar construction creates the pseudotensor . Mathematically, a pseudoscalar is an element of the top exterior power of a vector space , or the top power of a Clifford algebra see pseudoscalar Clifford algebra . More generally, it is an element of the canonical bundle of a differentiable manifold . Pseudoscalars in physics In physics , a pseudoscalar denotes a physical quantity analogous to a scalar physics scalar . Both are physical quantity physical quantities which assume a single value which is invariant under proper rotation s. However, under the parity transformation , pseudoscalars flip their signs while scalars do not. One of the most powerful ideas in physics is that physical laws do not change when one changes the coordinate system used to describe these laws. The fact that a pseudoscalar reverses its sign when the coordinate axes are inverted suggests that it is not the best object to describe a physical quantity. In 3 space, the Hodge dual of a scalar ... pseudotensor whereas the Hodge dual of a pseudoscalar is in fact a skew symmetric pure ... 3. Since the dual of the pseudoscalar is the product of two pseudo quantities it can be seen that the resulting ... dimensional spacetime of special relativity, a pseudoscalar is the dual of a fourth rank tensor which ... See also Pseudoscalar Clifford algebra A pseudoscalar in a geometric algebra is a highest graded ... 12 . math So a pseudoscalar is a multiple of e sub 12 sub . The element e sub 12 sub squares to 1 and commutes ... numbers . It is these scalar like properties which give rise to its name. In this setting, a pseudoscalar ... more details
Unreferenced stub auto yes date December 2009 Image Noneto mes nico de spin 0.png thumb The pseudoscalar mesons consisting of up, down, and strange quarks only form a nonet In high energy physics , a pseudoscalar meson is a meson with total angular momentum quantum number total spin 0 and odd Parity physics parity usually noted as J sup P sup 0 sup &minus sup . Compare to scalar meson . Pseudoscalar mesons are commonly seen in proton proton scattering and proton antiproton annihilation. The pion was first proposed to exist by Yukawa in the 1930s as the primary force carrying boson of the Yukawa Potential in nuclear interactions, and was later observed at nearly the same mass that he originally predicted for it. In the 1950s and 1960s, the pseudoscalar mesons began to proliferate, and were eventually organized into a multiplet according to Murray Gell Mann s so called Eightfold way physics Eightfold Way . Gell Mann further predicted the existence of a ninth resonance in the pseudoscalar multiplet, which he originally called X. Indeed, this particle was later found and is now known as the eta prime meson. The structure of the pseudoscalar meson multiplet, and also the ground state baryon multiplets, led Gell Mann and Zweig, independently to create the well known quark model. Among all of the mesons known to exist, the pseudoscalars are perhaps the most well known in a sense. The masses of the pion , kaon , Eta meson eta and Eta meson eta prime particles are known with great precision. However, the decay properties of the pseudoscalar mesons, particularly of eta and eta prime, are somewhat contradictory to the mass hierarchy. While the eta prime meson is much more massive than the eta meson, the eta meson is thought to contain a larger component of strange and anti strange ... brings glueball mixing into the discussion. It is possible that the eta and eta prime mesons mix with the pseudoscalar ... link yes top Eta See also List of mesons DEFAULTSORT Pseudoscalar Meson Category Mesons Particle ... more details
Unreferenced date December 2009 Pseudo Goldstone bosons arise in a quantum field theory with both spontaneous and explicit symmetry breaking. The controlling approximate symmetries , if they were exact, would be spontaneous symmetry breaking spontaneously broken hidden , and would thus engender massless Goldstone boson s. The additional explicit symmetry breaking gives these bosons a small mass. The properties of these pseudo Goldstone bosons can normally be found by an expansion around the exactly symmetric theory in terms of the explicit symmetry breaking parameters. Quantum chromodynamics QCD , the theory of strong particle interactions, provides the best known example in nature see the article on the QCD vacuum for details. Experimentally, it is observed that the masses of the octet of pseudoscalar physics pseudoscalar meson s such as the pion are very much lighter than the next heavier quantum state state s, ie, the octet of vector meson s such as the rho meson . In QCD, this is interpreted as a consequence of spontaneous symmetry breaking of chiral symmetry in a sector of QCD with 3 flavours of light quarks. Such a theory, for idealized massless quarks, has global math SU 3 times SU 3 math chiral flavour particle physics flavour symmetry. Under SSB, this is spontaneously broken to the diagonal SU 3 , generating eight Goldstone boson s, which are the pseudoscalar mesons transforming as an adjoint representation octet representation of flavour Special unitary group SU 3 . In actual full QCD, the small quark masses further break the chiral symmetry explicitly as well. The masses of the actual pseudoscalar meson octet are found by an expansion in the quark masses, which goes by the name of chiral perturbation theory . The internal consistency of this argument is further checked by lattice QCD computations, which allow one to vary the quark mass and check that the variation of the pseudoscalar masses with the quark masses is as dictated by chiral perturbation theor ... more details
Refimprove date December 2009 A scalar boson is a boson whose spin physics spin equals zero. Explanation The name scalar boson arises from quantum field theory . It refers to the particular transformation properties under Lorentz transformation . Boson means that it has an integer valued Spin physics Spin , the scalar fixes this value to 0. Examples One very popular quantum field theory, which uses scalar bosonic fields and is introduced in many introductory books to quantum field theories ref cite book author Michael E. Peskin and Daniel V. Schroeder title An Introduction to Quantum Field Theory publisher Westview Press year 1995 isbn 0 201 50397 2 ref for pedagogical reasons, is the so called Quartic interaction math Phi 4 math theory . It usually serves as toy model to introduce into the basic concepts of the field. The most famous example of a scalar boson in the Standard Model of Elementary particle physics is the Higgs boson , which is the only elementary particle which has not yet been experimentally measured October 2010 . Many mesons are scalar bosons. For them one distinguishes between the Scalar meson scalar and Pseudoscalar meson pseudoscalar mesons, which refers to their transformation property under Parity physics parity . One prominent representative of the pseodoscalar mesons is the Pion , some scalar mesons are interesting since they could be Exotic meson exotic . See also Scalar meson Pseudoscalar meson Quantum field theory Scalar field theory Vector boson References reflist DEFAULTSORT Scalar Boson Category Bosons Category Mesons Category Quantum field theory ... more details
Muon capture is the capture of a negative muon by a proton , usually resulting in production of a neutron and a neutrino , and sometimes a gamma ray gamma photon . Muon capture by heavy nuclei often leads to emission of particles most often neutron s, but charged particles can be emitted as well. Ordinary muon capture OMC involves capture of a negative muon from the atomic orbital without emission of a gamma photon SubatomicParticle muon SubatomicParticle Proton &rarr SubatomicParticle Neutrino SubatomicParticle Neutron0 Radiative muon capture RMC is a radiative version of OMC, where a gamma photon is emitted SubatomicParticle muon SubatomicParticle Proton &rarr SubatomicParticle Neutrino SubatomicParticle Neutron0 SubatomicParticle Gamma One motivation for the study of muon capture on the proton is its connection to the proton s induced pseudoscalar form factor g sub p sub . References cite journal author T. Gorringe and H.W. Fearing title Induced pseudoscalar coupling of the proton weak interaction journal Rev.Mod.Phys. year 2004 volume 76 pages 31&ndash 91 arxiv nucl th 0206039 doi 10.1103 RevModPhys.76.31 cite arxiv author V.A. Andreev et al. title Measurement of the Rate of Muon Capture in Hydrogen Gas and Determination of the Proton s Pseudoscalar Coupling g sub P sub year 2007 arxiv 0704.2072 Category Nuclear physics particle stub ... more details
wiktionarypar scalar Scalar may refer to Scalar mathematics , a quantity used to multiply vectors in the context of vector spaces Scalar physics , a quantity which is independent of specific classes of coordinate systems Scalar computing , an atomic quantity that can hold only one value at a time See also Scalar field Scalar prostoleg y Inner product space Scalar product, also known as the dot product Pseudoscalar Scalar processor Pterophyllum P. scalare Pterophyllum scalare Lichtenstein, 1823 , a species of freshwater angelfish disambig bs Skalar vor de Skalar es Escalar eo Skalaro fr Scalaire he ms Skalar pl Skalar ro Scalar sr sh Skalar ... more details
Image Primakoff effect diagram.GIF right thumb Feynman diagram representing the Primakoff effect. Primakoff effect after Henry Primakoff is the resonant production of neutral pseudoscalar meson s by high energy photon s interacting with an atomic nucleus . It can be viewed as the reverse process of the decay of the meson into two photons. Primakoff effect has been used for the measurement of the decay width of neutral mesons ref http www.slac.stanford.edu spires find hep www?j PRLTA,33,1400 The Decay Width of the Neutral Meson ref . Primakoff effect also could take place in stars, and be a production mechanism of hypothetical particles, such as the axion . The Primakoff effect is predicted to lead to optical properties of the vacuum state in the presence of a strong magnetic field. ref http arxiv.org abs hep ph 0701198v1 Resonantly enhanced axion photon regeneration P. Sikivie, D.B. Tanner, and Karl van Bibberc ref References references See also Vacuum state Category Particle physics de Primakoff Effekt pl Efekt Primakoffa ru physics stub ... more details
Unreferenced date June 2007 In high energy physics , a vector meson is a meson with total angular momentum quantum number total spin 1 and odd parity physics parity usually noted as nowrap J sup P sup 1 sup &minus sup . Compare to a pseudovector meson , which has a total angular momentum quantum number total spin 1 and even parity physics parity . Vector mesons have been seen in experiments since the 1960s, and are well known for their spectroscopic pattern of masses. Since the development of the quark model by Murray Gell Mann and independently by George Zweig as well , the vector mesons have demonstrated the spectroscopy of pure states. The fact that the nowrap Isospin I 1 rho meson &rho and nowrap I 0 omega meson &omega have nearly equal mass centered around 770 val 780 ul MeV c2 , while the phi meson &phi has a higher mass around val 1020 u MeV c2 , indicates that the light quark vector mesons appear in nearly pure states with the &phi meson having a nearly 100 percent amplitude of hidden strangeness . This characteristic of the vector mesons is not at all evident in the pseudoscalar meson or scalar meson multiplets, and may be only slightly realized among the tensor meson and pseudovector meson multiplets. This fact makes the vector mesons an excellent probe of the quark flavour physics flavor content of other types of mesons, measured through the respective decay rate s of non vector mesons into the different types of vector mesons. Such experiments are very revealing for theorists who seek to determine the flavor content of mixed state mesons. At higher masses, the vector mesons include charm quark charm and bottom quark s in their structure. In this realm, the radiative process es tend to stand out, with heavy tensor and scalar mesons decaying dominantly into vector mesons by photon emission . Pseudovector mesons transition by a similar process into pseudoscalar mesons. Because much of the spectrum of heavy mesons is tied by radiative processes to the vector ... more details
In theoretical physics , the Wess Zumino model has become the first known example of an interacting four dimensional quantum field theory with supersymmetry , at least in the Western world. In 1974, Julius Wess and Bruno Zumino studied, using modern terminology, dynamics of a single chiral superfield composed of a complex scalar physics scalar and a spinor fermion whose cubic superpotential leads to a renormalizable theory. Introduction The Lagrangian of the free massless Wess Zumino model in four dimensional spacetime with flat metric math mathrm diag 1,1,1,1 math is math mathcal L frac 1 2 partial S 2 frac 1 2 partial P 2 frac 1 2 bar psi partial psi math with math S math a scalar field, math P math a pseudoscalar field and math psi math a Dirac spinor field. The action is invariant under the transformations generated by the superalgebra. The infinitesimal form of these transformations is math delta epsilon S bar epsilon psi math math delta epsilon P bar epsilon gamma 5 psi math math delta epsilon psi partial S P gamma 5 epsilon math where math epsilon math is a Majorana spinor valued transformation parameter and math gamma 5 math is the Chirality physics Chiral theories chirality operator . Invariance under a modified set of supersymmetry transformations remains if one adds mass terms for the fields, provided the masses are equal. It is also possible to add interaction terms under some algebraic conditions on the coupling constants, resulting from the fact that the interactions come from superpotential for the chiral superfield containing the fields math S math , math P math and math psi math . References J.M. Figueroa O Farrill, Busstepp Lectures on Supersymmetry http arxiv.org abs hep th 0109172 . J. Wess, B. Zumino, Supergauge transformations in four dimensions http adsabs.harvard.edu abs 1974NuPhB..70...39W Quantum field theories Category Supersymmetry quantum stub ko it Modello di Wess Zumino ... more details
mathbf a times mathbf c math Scalar or pseudoscalar Although the scalar triple product gives the volume ... , and so is more properly described as a pseudoscalar if the orientation can change. This also ... is a pseudoscalar, so the scalar triple product must be pseudoscalar valued. As an exterior ... triple product, and is the pseudoscalar dual of the triple product. As the exterior product ... more details
algebra over C . When n is odd, the center includes not only the scalars but the pseudoscalar mathematics pseudoscalar s degree n elements as well. We can always find a normalized pseudoscalar such that ... to 1 and q vectors which square to &minus 1. Unit pseudoscalar See also Pseudoscalar The unit pseudoscalar in C sub p , q sub R is defined as math omega e 1e 2 cdots e n. math This is both a Coxeter ... for the trivial quadratic form, the unit pseudoscalar is a volume form , and lifts reflection through the origin meaning that the image of the unit pseudoscalar is reflection through the origin, in the orthogonal ... a pseudoscalar which squares to 1. Center If n is even equivalently, if p &minus q is even the algebra ... more details
id arxiv astro ph 0409121 ref scalar and pseudoscalar dark matter ref name bern2 cite journal author R. Bernabei et al. year 2006 title Investigating pseudoscalar and scalar dark matter journal ... more details
In particle physics , Yukawa s interaction , named after Hideki Yukawa , is an interaction between a scalar field quantum field theory scalar field math phi math and a Dirac field math Psi math of the type math V approx g bar Psi phi Psi math scalar or math g bar Psi gamma 5 phi Psi math pseudoscalar . The Yukawa interaction can be used to describe the strong nuclear force between nucleon s which are fermion s , mediated by pion s which are pseudoscalar meson s . The Yukawa interaction is also used in the Standard Model to describe the coupling between the Higgs field and massless quark and electron fields. Through spontaneous symmetry breaking , the fermions acquire a mass proportional to the vacuum expectation value of the Higgs field. The action The action physics action for a meson field interacting with a Dirac fermion field is math S phi, psi int d dx left mathcal L mathrm meson phi mathcal L mathrm Dirac psi mathcal L mathrm Yukawa phi, psi right math where the integration is performed over d dimensions typically 4 for four dimensional spacetime . The meson Lagrangian is given by math mathcal L mathrm meson phi frac 1 2 partial mu phi partial mu phi V phi math . Here, math V phi math is a self interaction term. For a free field massive meson, one would have math V phi mu 2 phi 2 math where math mu math is the mass for the meson. For a renormalizable self interacting field, one will have math V phi mu 2 phi 2 lambda phi 4 math where is a coupling constant. This potential is explored in detail in the article on the quartic interaction . The free field Dirac Lagrangian is given by math mathcal L mathrm Dirac psi bar psi i partial m psi math where m is the positive, real mass of the fermion. The Yukawa interaction term is math mathcal L mathrm Yukawa phi, psi g bar psi phi psi math where g is the real coupling constant for scalar mesons and math mathcal L mathrm Yukawa phi, psi g bar psi gamma 5 phi psi math for pseudoscalar mesons. Putting it all together ... more details
Orphan date February 2009 Deleted image removed Image KALBFLEISCH.jpg right thumb George Randolph Kalbfleisch puic Image KALBFLEISCH.jpg log 2008 July 5 Dr. George Randolph Kalbfleisch March 14, 1931&ndash September 12, 2006 was a US particle physicist . George Kalbfleisch was born March 14, 1931 in Long Beach, California, to Friedrich Carl and Hildegard Kalbfleisch. He graduated from Phineas Banning High School, Wilmington, California, in 1948. He received his Bachelor of Science degree in chemistry from Loyola University, Los Angeles, California, in 1952. On October 23, 1954, he married Ruth Ann Adams in San Pedro, California. He received his Ph.D. in experimental High Energy Physics in 1961 from the University of California at Berkeley . He worked as a post doctoral associate at the University of California at Berkeley with Dr. Luis Alvarez , as a staff physicist at Brookhaven National Laboratory on Long Island, New York, for twelve years, and at Fermi National Laboratory Fermilab in Batavia, Illinois, for three years. He performed experiments in the systematizing and the discovery of new particles since 1958, using beams of muons , pions , kaons , protons and antiprotons , and neutrinos . He worked with liquid hydrogen bubble chamber s until 1972, and subsequently worked with electronic spectrometers. He performed research at CERN Laboratory in Switzerland during a sabbatical in 1972. While at Fermilab, he was in charge of the superconducting quadrupoles for the Tevatron at that time, the world s highest energy machine , built more than twenty prototype quadrupoles, and developed and provided the production tooling from which more than 200 quadrupoles were made for the Tevatron . Dr. Kalbfleisch came to the University of Oklahoma OU in 1979 where he established the OU High Energy Physics group OU HEP . He was elected as a Fellow in the American Physical Society in 1982 for his discoveries of the first hyperonic beta decay, of the ninth pseudoscalar meson, the fi ... more details
with pseudoscalar fields. Uses in physics In physics, scalar fields often describe the potential ..., pions are actually examples of pseudoscalar mesons , which fail to be invariant under spatial ... more details
. The Goldstone boson s of the symmetry breaking are the pseudoscalar physics pseudoscalar meson ... pseudoscalar meson s of the quark model become Goldstone boson s. The actual masses of these meson s are obtained ... is the Yukawa coupling to a pseudoscalar math L I bar N gamma 5 pi N , math And this is clearly ... pi rightarrow pi C , math leaves the gradient coupling alone, but not the pseudoscalar coupling ... of pseudoscalar mesons is very much lighter than the next lightest states i.e., the octet of vector ... of the pseudoscalar masses with the quark mass is as required by chiral perturbation ... of the mysteries of the quark model where all the pseudoscalar mesons should have been of nearly the same ... more details
2, i gamma 3 math and one pseudoscalar math i gamma 0 gamma 1 gamma 2 gamma 3 math . Reciprocal frame ... pseudoscalar, and others have extended this to provide a framework for locally varying vector ... more details
vector fields, pseudovector fields are 2 vector fields, and pseudoscalar fields are 3 vector fields. In higher dimensions there are additional types of fields scalar vector pseudovector pseudoscalar ... more details
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