Generating fermion mass in four-dimensional quenched QED

Abstract

The fermion propagator in four-dimensional quenched QED is studied by way of its Schwinger-Dyson equation. The all important fermion-boson vertex is approximated by a nonperturbative form that satisfies the Ward-Takahashi identity and ensures the fermion is multiplicatively renormalizable. Numerical solutions in both the Landau and Feynman gauges show a dynamical mass is generated for all values of the coupling.