On the Equivalence of Unitary · and Renormalizahle-Gauge Formulations of a Massive Gauge Theory

By the use of the n-dimensional regularization method, the equivalence of the U- and R-gauge formulations is examined in low-order Green's functions for the-Abelian-gauge-field model. Intensively used are the formulae which express a U-gauge Green's function in terms of the R-gauge ones. The occurrence of the U-gauge residual divergences and their can-cellations in the S-matrix are then naturally understood in comparison with the R-gauge formulation. § 1. Introduction an