He-Shan Song

Statistical mechanical properties of the q-oscillator system

The q-deformed thermofield dynamics is constructed and in terms of this dynamics some statistical mechanical properties of a system of q-harmonic oscillators are discussed.

ONE WAY TO SOLVE THE PUZZLE OF GAMMA-5 IN THE DIMENSIONAL REGULARIZATION

By calculating the Dirac matrices in four dimensions and performing the dimensional regularization for loop momentum integration variables, various Ward identities can be obtained straightforwardly and the puzzle for extending γ5 to n dimensions can be solved.

A PHYSICAL EXPLANATION FOR THE TILDE SYSTEM IN THERMO FIELD DYNAMICS

For a two-body quantum system, any pure state can be represented by a biorthogonal expression by means of Schmidt decomposition. Using this in the composite system which includes a thermodynamic system and its surroundings, it is found that the tilde system in thermo field dynamics is just the surroundings of the real system.

General Deformation Scheme of Heisenberg-Weyl Algebra*

General deformation schemes for both bosonic and fermionic algebras of harmonic oscillator are studied in terms of explicit matrix representations of basic operators and a restriction relation for deformation function is discussed.

Dynamical Symmetry Breaking for Weinberg–Salam Model and Restoration at Finite Temperature

In this paper, we utilize Nambu-Jona-Lasinio (NJL) mechanism to discuss the dynamical symmetry breaking for Weinberg-Salam model. In the NJL mechanism the symmetry breaking not only is determined by the potential of scalar field but also has important relation with condensate of the fermion pair . We find that the coefficient of quadric term of scalar field can still cause symmetry breaking by virtue of , and the vacuum expected value of scalar field obeys , i.e., the order parameter which causes phase transition is the condensate of fermion pair . We also discuss the restoration problem of gauge symmetry breaking by the NJL mechanism at high temperatures.

Statistical Distribution of q-Bosonic Oscillators*

The statistical distribution for a system of q-deformed harmonic oscillators is studied and an explicit form of q-dependence of the distribution function is given. The physical meaning of the deformation parameter q is discussed.

CHIRAL SYMMETRY RESTORATION IN LATTICE GAUGE-THEORY

The pion mass calculated starting from the strongly coupling effective Hamiltonian for Wilson fermions by using Green function method. The possibility of the chiral symmetry restoration at a critical quark mass is also investigated.

CHARGED VORTICES IN AN ABELIAN HIGGS-MODEL WITH CHERN-SIMONS TERM AT FINITE-TEMPERATURE

Charged vortex solutions are found in a -dimensional Abelian Higgs model with Chern-Simons term at finite temperature. It is shown that there exists a finite critical temperature at which vortices disappear and it implies that the system changes from superconducting state to normal state at this critical temperature.

Anyon Solution of an Abelian Gauge Field Coupling with Torsion

Anyon solution of an Abelian gauge field coupling with torsion of spacetime is given. It is shown that the torsion contributes to the spin and mass of the anyon proportionally. The orders of them on the surface of general neutron star are estimated in NGR theory.

Chern-Simons Gauge Theory and Ginzburg-Landau Type Theories (II) Non-Abelian Cases*

We show that after the spontaneous symmetry breaking has taken place the Abelian Higgs models with or without the Chern-Simons term would satisfy the same field equation with the massive Chern-Simons gauge theory and have the same anyon solutions. So we regard the massive Chern-Simons gauge theory as an effective gauge theory of the Abelian Higgs models.