The Pinch Technique Approach to the Physics of Unstable Particles

TL;DR

This paper applies the pinch technique at one-loop level to improve the theoretical description of unstable particles in gauge field theories, ensuring physical consistency in off-shell Green's functions.

Contribution

It introduces a method using the pinch technique to properly define and resum off-shell Green's functions for unstable particles at one-loop order.

Findings

Provides a consistent one-loop framework for unstable particles

Ensures gauge invariance and physical requirements in Green's functions

Enhances theoretical tools for particle physics calculations

Abstract

The consistent description of unstable particles within the framework of perturbative gauge field theories necessitates the definition and resummation of off-shell Green's functions, which must respect several crucial physical requirements. We present the solution to this problem at one-loop, using the pinch technique.