Chou Kuang-chao

On the gauge invariance and anomaly-free condition of the Wess-Zumino-Witten effective action

A global anomaly-free condition and a non-abelian gauge invariant Wess-Zumino-Witten effective action with less terms have been found by a systematical method rather than by trial and error. The condition requires the difference between the left- and right-handed Chern-Simon five-forms wrt the gauge group must vanish and it turns out to be the usual condition in the local sense.

On the Two Dimensional Non-Linear σ Model with Wess-Zumino Term II Quantum Theory

The canonical quantization is carried out for the two dimensional non-Linear σ model with Wess-Zumino term. It is shown that the currents in this model satisfy a Kac-Moody algebra for arbitrary values of the coupling constant.

On the Two-Dimensional Non-Linear σ Model with Wess-Zumino Term

The classical solutions of the two-dimensional non-linear σ model with Wess-Zumino term are shown to be equivalent to that without the Wess-Zumino term under a suitable transformation.

ON THE DYNAMICAL PROBLEMS AND THE FERMION SPECTRA IN THE RISHON MODEL

We propose to introduce a strong coupling U(l)y axial gauge boson into the rishon model which may explain dynamical problems concerning preservation of chiral symmetries and existence of solutions to anomaly conditions. Mechanisms through which exotic particles gain masses are discussed. It is found that exotic particles such as color octet leptons and color sextet quarks may gain masses ranging from 10 1 to 103. Some phenomenological aspects of these exotic particles are discussed.

The Hn Sigma-Models and Self-Dual SU(n) Yang-Mills Fields In Four-Dimensional Euclidean Space

The Hn σ-models, i.e., non-linear σ-models taking-values on the symmetric coset space SL(n,c)/SU(n), both in two-dimensional and four-dimensional Euclidean space, are formulated. The relations with self-duel SU(n) Yang-Mills fields are also discussed.

On an Approximate Form of the Coupled Equations of the Order Parameter with the Weak Electromagnetic Field for the Ideal Superconductor

A simplified derivation of, the macroscopic electrodynamic equations of Umezawa, Mancini et al. for superconductors is given in the framework of the closed time path Greens functions (CTPGF) using generalized Ward-Takahashi identities. It is shown that the forms of the equations obtained are the same for both thermo-equilibrium and nonequilibrium stationary states provided the electromagnetic field is weak and its effect on the modulus of the order parameter can be neglected. The statistical behavior of the states is completely specified in the equations by parameters which can be calculated by the method of CTPGF.

A Simplified Derivation of Chern-Simons Cochain and a Possible Origin of θ-Vacuum Term

In this paper, it is shown that the cohomology of generalized secondary classes, the Faddeev type cohomology and the generalized gauge transformation can be easily obtained by expanding the Chern form according to the degree of the forms in its submanifolds and using the closed property of the Chern form. It is also shown that a θ-vacuum term in the effective Lagrangian arises when gauge field in the group manifold is present.

GENERALIZED GAUGE TRANSFORMATION AND CHERN SIMONS COCHAIN

A gauge potential defined on group manifold is defined to generalize the gauge transformation. Some symmetry properties and a generalized Chern-Simons cochain are formed.

On Witten's Effective Lagrangian for Chiral Field

Wess and Zuminos effective Lagrangian for the chiral field is derived by a new method which shows the direct relationship between the Lagrangian and the difference of the left handed and right handed Chern-Simons topological invariants. The resulting Lagrangian is explicitly left and right antisymmetric and equal to the one obtainedin a previous letter by a different method.

The Topolosical Origins of Gauge Anomalies

In addition to the recent discovery that the Chern-Simons secondary classes are the topological origins generating special unitary gauge group anomalies, it is shown that some special orthogonal gauge group anomalies can also be generated, from the Pontrjagin and the Euler secondary classes. The common differential geometrical and topological background are explained as well.