Selection rules in strong interactions

Abstract

The invariances under P-and T-transformations in the electromagnetic and the mesonic interactions are discussed using the generalized Dirac equation obtained by assuming invariance only under the proper Lorentz transformation. It is shown that the existence of P-and T-invariance in the above interactions is based on the fact that the theories must be invariant under the extended gauge-like transformations. The strong mesonic interactions are found to be derivative. The “principle of the minimal electromagnetic interaction” and the assumption of the “global symmetry” for the strong mesonic interactions are naturally obtained from our standpoint.