The Pinch Technique to All Orders

Abstract

The generalization of the pinch technique to all orders in perturbation theory is presented. The effective Green's functions constructed with this procedure are singled out in a unique way through the full exploitation of the underlying Becchi-Rouet-Stora-Tyutin symmetry. A simple all-order correspondence between the pinch technique and the background field method in the Feynman gauge is established.

Comments: 10 pages, 4 figures; one reference added, typos corrected; final version to match the pubblished one