Cosmological background torsion inhomogeneities and Lorentz violation in QED

TL;DR

This paper investigates how cosmological torsion inhomogeneities affect photon propagation in QED, revealing Lorentz violation and massive photon modes in a torsion-rich spacetime, with implications for fundamental physics.

Contribution

It introduces a non-minimal photon-torsion coupling in QED and analyzes its effects on photon propagation, highlighting Lorentz violation and photon mass generation in a cosmological torsion background.

Findings

Torsion inhomogeneities induce Lorentz violation in photon propagation.

Vacuum polarization effects alter photon behavior in torsionic backgrounds.

Massive photon modes emerge due to torsion effects.

Abstract

A non-minimal photon-torsion axial coupling in the quantum electrodynamics (QED) framework is considered. The geometrical optics in Riemann-Cartan spacetime is considering and a plane wave expansion of the electromagnetic vector potential is considered leading to a set of the equations for the ray congruence. Since we are interested mainly on the torsion effects in this first report we just consider the Riemann-flat case composed of the Minkowskian spacetime with torsion. It is also shown that in torsionic de Sitter background the vacuum polarisation does alter the propagation of individual photons, an effect which is absent in Riemannian spaces. It is shown that the cosmological torsion background inhomogeneities induce Lorentz violation and massive photon modes in this QED.