The Running Gauge Coupling in the Exact Renormalization Group Approach

We discuss the perturbative running Yang-Mills coupling constant in the Wilsonian exact renormalization group approach, and compare it to the running coupling in the more conventional MS-bar scheme. The exact renormalization group approach corresponds to a particular renormalization scheme, and we relate explicitly the corresponding Lambda-parameters. The unambiguous definition of an exact renormalization group scheme requires, however, the use of a one-loop improved high energy effective action.