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1.
The SU(3) polarization theory in the Hilbert space is developed for quantum Bose systems with Gell-Mann symmetry. The degrees of polarization and isopolarization are determined. An original SU(3) interferometer for measuring the phase-dependent Gell-Mann parameters of an optical field is considered, and the signal-to-noise measurements limiting in quantum noises and based on the use of entangled and squeezed states of light at the entrance of the optical system are analyzed. A new type of quantum (helical) states of optical radiation for which the correlation between the Hermitian quadratures and isospin operators plays a crucial role is revealed for one of these modes in the classical-field approximation.  相似文献   

2.
An algebraic realization of SU(3) × SU(3) symmetry, with linearization on the SU(2) × Y subgroup taking into account masses of π, K, η mesons in virtual states is investigated. This is achieved by explicit breaking of the symmetry. The chosen form of the breaking term in the Lagrangian enables us to estimate the parameter c appearing in the squared mass operator. The obtained value of c(c ≈ ?1.17) is very close to that predicted by Gell-Mann, Oakes and Renner.  相似文献   

3.
The many-current Ward identities corresponding to the Gell-Mann current algebra are discussed in the renormalized model. The Ward identities are verified in the case of the SU(2)×SU(2) chiral symmetry. In the SU(3)×SU(3) case the uniqueness of the Adler-Bardeen anomaly is proved using the Wess-Zumino consistency conditions.On leave of absence from the University of Genova (Italy).Chercheur Associé au C.N.R.S. (C.P.T./Marseille).  相似文献   

4.
Relations connecting the effective bare current-quark masses with asymptotic meson-nucleon and lepton-nucleon scattering are derived by making use of the extended light-cone algebra which includes commutators of pseudoscalar densities. The commutators are relevant to meson-nucleon scattering amplitudes since the pseudoscalar densities act as fields of the (composite) mesons. Assuming pomeron-exchanged Regge behaviour, sufficient analyticity in the meson mass-squared variable is established to obtain finite-mass dispersion and superconvergence relations. Making additionally certain other reasonable assumptions, we are then able to show how these relations yield testable connections among the asymptotic πN and KN total cross sections, the structure functions of the deep inelastic lepton-nucleon scattering (for the scaling variable, ξ →0) and the bare current-quark masses μp, n, λ that appear essentially as parametrising the breaking of the chiral SU(3) ? SU(3) symmetry. One interesting consequence of our results is at the Llewellyn-Smith inequality on the said structure functions should be experimentally satisfied as a near equality for ξ → 0, if chiral SU(2) ? SU(2) turns out to be a rather good symmetry of nature. Moreover, taking the specific symmetry breaking model of Gell-Mann Oakes and Renner,we find that μp, n ≈ 35 MeV and μλ ≈ 800 MeV.  相似文献   

5.
We explore the possibility that high energy physics is an infrared phenomenon, with strong interactions determined by an infrared stable fixed point of the renormalisation group. Models ofφ3 interactions with SU(n) and SU (3) ×SU (3) internal symmetries are shown to illustrate this idea. Corrections to a Gell-Mann Okubo mass formula are calculated to first order in ? in 6?? dimensions.  相似文献   

6.
王海军 《中国物理 C》2009,33(6):487-493
In this paper we postulate an algebraic model to relate the triplet characteristic of lepton families to Lorentz violation. Inspired by the two-to-one mapping between the group SL(2, C) and the Lorentz group via the Pauli grading (the elements of SL(2, C) expressed by direct sum of unit matrix and generators of SU(2) group), we grade the SL(3,C) group with the generators of SU(3), i. e. the Gell-Mann matrices, then express the SU(3) group in terms of three SU(2) subgroups, each of which stands for a lepton species and is mapped into the proper Lorentz group as in the case of the group SL(2,C). If the mapping from group SL(3,C) to the Lorentz group is constructed by choosing one SU(2) subgroup as basis, then the other two subgroups display their impact only by one more additional generator to that of the original Lorentz group. Applying the mapping result to the Dirac equation, it is found that only when the kinetic vertex -γμθ^μ is extended to encompass γ5γμθ^μ can the Dirac-equation-form be conserved. The generalized vertex is useful in producing neutrino oscillations and mass differences.  相似文献   

7.
Using the recently derived Evans wave equation of unified field theory, the strong nuclear field is described with an SU(3) representation of the gravitational field and the Gell-Mann color triplet is derived from general relativity as a three-spinor eigenfunction of the Evans wave equation.  相似文献   

8.
The apparent anticorrelation between the solarneutrino flux and the sun-spot number can be explained if electron neutrino has a large magnetic moment. A model with SU(2) L ×SU(2) R ×U(1) B?l gauge interaction is presented in which the electron neutrino has a large magnetic moment. The ingredients of the model are (i) the absence of the usual discrete left-right symmetry, (ii) new fermions that are singlets under SU(2) L and SU(2) R and (iii) two doublets and a charged singlet of higgs. The model utilises the see-saw mechanism of Gell-Mann, Ramond and Slansky give masses to all quarks and leptons. The large magnetic moment of the electron neutrino is achieved through charged singlet higgs fields.  相似文献   

9.
We study the topological structure of thesymmetry group of the standard model, GSM =U(1) × SU(2) × SU(3). Locally,GSM S1 ×(S3)2 × S5. For SU(3), whichis an S3-bundle over S5 (and therefore a local product of thesespheres) we give a canonical gauge i.e., a canonical setof local trivializations. These formulas give explicitlythe matrices of SU(3) without using the Lie algebra (Gell-Mann matrices). Globally, we prove thatthe characteristic function of SU(3) is the suspensionof the Hopf map . We also study the case of SU(n) forarbitrary n, in particular the cases of SU(4), a flavor group, and of SU(5),a candidate group for grand unification. We show thatthe 2-sphere is also related to the fundamentalsymmetries of nature due to its relation to SO0(3, 1), the identity component of the Lorentz group, asubgroup of the symmetry group of several gauge theoriesof gravity.  相似文献   

10.
A quark meson coupling model based on SU(3)L×SU(3)R symmetry and scale invariance is proposed. The quarks and mesons get masses through symmetry broken. We apply this SU(3) chiral constituent quark model to investigating the nuclear matter at finite temperature and density. The effective baryon masses, compression modulus and hyperon potentials are all reasonable. The critical temperature of liquid-gas phase transition is also calculated in this model.  相似文献   

11.
In this paper, generalizations of the Stokes parameters and alternative characterizations of three-dimensional (3D) time-varying electromagnetic fields is introduced. One of these characteristics is the normal of the polarization plane, which, in many cases of interest, is parallel (or antiparallel) to the direction of propagation. Others are the two spectral density Stokes parameters which describe spectral intensity and circular polarization. The analysis is based on the spectral density tensor. This tensor is expanded in a base composed of the generators of the SU(3) symmetry group, as given by Gell-Mann and Y. Ne'eman [The Eight-fold Way (Benjamin, New York, 1964)] and the coefficients of this expansion are identified as generalized spectral density polarization parameters. The generators have the advantage that they obey the same algebra as the Pauli spin matrices, which is the base for expanding the 2D spectral density tensor with the Stokes parameters as coefficients. The polarization parameters introduced are formulated in the frequency domain, thereby further generalizing the theory to allow for wide-band electromagnetic waves in contrast to the traditional quasi-monochromatic formulation.  相似文献   

12.
We associate SU(3) breaking of strong interactions with superfluidity of hadronic matter. At high energies and large transverse momenta a phase transition occurs and SU(3) becomes an exact symmetry.  相似文献   

13.
We propose a geometrical formulation of complementarity between the Higgs phase and the confining phase of a non-abelian gauge theory, introducing local “vierbein” fields to provide for a one-to-one mapping between the states of the two phases. We investigate the gauge structure when a subgroup of the global symmetry is also gauged. The formalism is used to build up a composite model based on a SU(4) of subcolor complementary to a Pati-Salam SU(4), and allowing for dynamical symmetry breaking of SU(2)L ? U(1).  相似文献   

14.
The basic role of the representation of the gauge group in characterizing the topological excitations of the vacuum is pointed out. For SU(N) gauge fields on a lattice, the topological excitations are monopoles in the adjoint representation of the dual group 1SU(N). This leads to a dual representation of the Yang-Mills-Higgs system in 2 + 1 dimensions. For SU(3) the deal theory in a scalar theory with discrete Weyl symmetry S3. In the presence of adjoint Higgs fields the Weyl symmetry is broken in the Higgs phase but restored by pseudo-particles in the confinement phase.  相似文献   

15.
We show that in the non-linear σ-model, we have a phase transition when the isospin chemical potential is equal to the meson mass. This result is shown to be generally true in the SU(2)×SU(2) symmetry breaking model.  相似文献   

16.
In this paper we postulate an algebraic model to relate the triplet characteristic of lepton families to Lorentz violation. Inspired by the two-to-one mapping between the group SL(2, C) and the Lorentz group via the Pauli grading (the elements of SL(2, C) expressed by direct sum of unit matrix and generators of SU (2) group), we grade the SL(3, C) group with the generators of SU(3), i. e. the Gell-Mann matrices, then express the SU(3) group in terms of three SU(2) subgroups, each of which stands for a lepton species and is mapped into the proper Lorentz group as in the case of the group SL(2,C). If the mapping from group SL(3,C) to the Lorentz group is constructed by choosing one SU(2) subgroup as basis, then the other two subgroups display their impact only by one more additional generator to that of the original Lorentz group. Applying the mapping result to the Dirac equation, it is found that only when the kinetic vertex γμξμ is extended to encompass γμξμ can the Dirac-equation-form be conserved. The generalized vertex is useful in producing neutrino oscillations and mass differences.  相似文献   

17.
We review the physical concepts supporting the notion of an approximate hadron symmetry with special emphasis on the Nambu-Goldstone realizations of chiral SU (2) × SU (2) and SU (3) × SU (3). We stress the role of perturbation theory in the symmetry breaking as the technical instrument to connect broken symmetries with experiment. This is an alternate to the treatments that stress PCAC and current algebra. We find that chiral SU (2) × SU (2) is a good hadron symmetry to within 7% making it the best hadron symmetry after isotopic symmetry. The nonrenormalization theorem, Σ-terms, Kl3 decay, η→3π decay, the Goldberger-Treiman relation and many other specific processes and their relation to approximate chiral symmetry are discussed.  相似文献   

18.
A grand unified gauge theory based on the group SU(8) is presented. The set of rules motivating the choice of SU(8) is given. The particle content of the theory suggests a natural embedding of a horizontal SU(3) symmetry in the SU(8) grand unified symmetry.  相似文献   

19.
The QCD deconfinement phase transition in pure SU(3) gauge theory is studied on an anisotropic lattice. The critical temperature is determined to be Tc ≈ 285 MeV. The relation between the deconfinement phase transition and the breakdown of Z(3) center symmetry is also discussed.  相似文献   

20.
We study the long-distance behaviour of pure unified SU(5) gauge theory in the limit when the electroweak subgroup is unbroken. We show that the symmetry breaking pattern SU(5)→SU(3)c×SU(2)×U(1)Y, with SU(3)c and SU(2) ×U(1)Y realized, respectively, in confining and coulombic phases, is a possible dynamical phase of the SU(5) theory. The proof relies on showing that the duality equation of 't Hooft, relating the electric and magnetic flux, is exactly satisfied for the above symmetry breaking pattern. The infrared structure of SU(5), broken down to SU(3)c×SU(2)×U(1)Y, is not self-dual.  相似文献   

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