A new CPT-even and Lorentz-Violating nonminimal coupling in the Dirac equation

TL;DR

This paper introduces a novel CPT-even, Lorentz-violating nonminimal coupling in the Dirac equation, leading to new physical effects and allowing stringent experimental constraints on the coupling strength.

Contribution

It proposes a new dimension-five nonminimal coupling involving Lorentz violation, modifying the Dirac equation and predicting observable effects.

Findings

Predicts electric-Zeeman-like spectrum splitting

Identifies an anomalous contribution to electron magnetic moment

Constrains the coupling magnitude to 1 part in 10^16

Abstract

In this work, we propose a CPT-even and Lorentz-violating dimension-five nonminimal coupling between fermionic and gauge fields, involving the CTP-even and Lorentz-violating gauge tensor of the SME. This nonminimal coupling modifies the Dirac equation, whose nonrelativistic regime is governed by a Hamiltonian which induces new effects, such as an electric-Zeeman-like spectrum splitting and an anomalous-like contribution to the electron magnetic moment, between others. Some of these new effects allows to constrain the magnitude of this nonminimal coupling in 1 part in 10^16.