Mass reversal and the universal interaction

Abstract

It is assumed that the results of relativistic quantum theories should be invariant under the change in sign of the mass term in the Dirac Equation. The consequences of this principle for the Universal Fermi Interaction are that only mixtures of scalar, pseudoscalar and tensor (S, P, T) interactions or mixtures of vector and axial vector interactions (V, A) are possible. Thus no Fierz interferences are allowed. In order to obtain further restrictions on the Fermi interaction, symmetry principles of the kind proposed byPursey are considered. It is found that the only possible interactions are the following mutually excluding ones: (S+P±T), (A±V), (S+P±T/3), (S, P),A, V andT.