The One Loop Effective Action of QED for a General Class of Electric Fields

Abstract

We compute the effective action of QED at one loop order for an electric field which points in the $\hat{z}$ direction and depends arbitrarily upon the light cone time coordinate, $x^{+}=(x^0+x^3)/\sqrt{2}$. This calculation generalizes Schwinger's formula for the vacuum persistence probability in the presence of a constant electric field.

Comments: 9 pages, LaTeX 2 epsilon