# Lorentz Violation and Radiative Corrections in Gauge Theories

## TL;DR

This paper reviews Lorentz-violating radiative corrections in gauge theories, clarifies conventions in the Standard-Model Extension, and improves bounds on Lorentz-violating coefficients through loop correction analysis.

## Contribution

It clarifies the conventions used in Lorentz-violating models and provides an improved bound on a specific Lorentz-violating coefficient in QED.

## Key findings

- Identified inconsistencies in previous literature conventions.
- Demonstrated a loop correction to the $k_{F}$ coefficient.
- Improved bounds on a Lorentz-violating fermion sector coefficient.

## Abstract

Various studies have already considered radiative corrections in Lorentz-violating models unveiling many instances where a minimal or nonminimal operator generates, via loop corrections, a contribution to the photon sector of the Standard-Model Extension. However, an important fraction of this literature does not follow the widely accepted conventions and notations of the Standard-Model Extension, and this obscures the comparison between different calculations as well as possible phenomenological consequences. After reviewing some of these works, we uncover one example where a well defined loop correction to the $k_{F}$ coefficient, already presented in the literature, allows us to improve the bounds on one specific coefficient of the fermion sector of the Lorentz-violating QED extension.