Infra-red Divergences in Light-Front QED and Coherent State Basis

TL;DR

This paper demonstrates that using a coherent state basis in Light-Front QED cancels infrared divergences in electron mass renormalization calculations up to second order in the coupling constant.

Contribution

It introduces a method to cancel infrared divergences in LFQED by employing a coherent state basis instead of the traditional Fock basis.

Findings

Infrared divergences are canceled up to O(e^4) using the coherent state basis.

The approach improves the accuracy of mass renormalization calculations in LFQED.

Coherent states effectively handle infrared issues in light-front quantum field theories.

Abstract

We present a next to leading order calculation of electron mass renormalization in Light-Front Quantum Electrodynamics (LFQED) using old-fashioned time ordered perturbation theory (TOPT). We show that the true infrared divergences in $\delta m^2$ get canceled up to $O(e^4)$ if one uses coherent state basis instead of fock basis to calculate the transition matrix elements.