Wilson renormalization group and improved perturbation theory

Abstract

We discuss a resummed perturbation theory based on the Wilson renormalization group. In this formulation the Wilsonian flowing couplings, which generalize the running coupling, enter directly into the loop expansion. In the case of an asymptotically free theory the flowing coupling is well defined since the infrared Landau pole is absent. We show this property in the case of the $\phi^3_6$ theory. We also extend this formulation to the QED theory and we prove that it is consistent with gauge invariance.