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 Feddeev type cohomology and he generalized gauga 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.