On conditions for the nonperturbative equivalence of ultraviolet cut-off and dimensional regularization schemes

Abstract

We consider procedures through which an ultraviolet cut-off regularization scheme can be modified to reproduce the same results for nonperturbative renormalized Green's functions as obtained from a dimensional regularization scheme. These issues are considered within the Dyson-Schwinger equation framework, where ultraviolet cut-off regularization can lead to explicit violations of gauge invariance. As a specific illustration, we consider the electron self-energy in quenched QED_4 in both schemes and establish those procedures for which the UV cut-off scheme can be expected to lead to the dimensional regularization results. We also compare results from precise numerical studies using the two types of regularization.