RENORMALIZATION-GROUP APPROACH TO FIELD-THEORY

Renormalization group flow equations are obtained for both scalar and gauge theories using a manifestly symmetry preserving regularization p rocedure similar to the proper-time formalism. In our scheme the regul arization is achieved by the smooth suppression of the large eigenvalu es in the quantum fluctuation determinants. With appropriate choice of the suppression factor this method incorporates the features of a sha rp momentum cut-off and renders the calculation finite throughout. The similarity of this cut-off to the Pauli-Villars regulator in the ultr aviolet regime is explicitly demonstrated. Our approach can be readily implemented to Yang-Mills theory without spoiling gauge symmetry.