Maxwell-Kosteleck\'y Electromagnetism and Cosmic Magnetization

TL;DR

This paper explores how Lorentz-violating modifications to electromagnetism during inflation can amplify magnetic fields, potentially explaining the observed large-scale cosmic magnetization.

Contribution

It demonstrates that the Kostelecký Lorentz-violating term can break conformal invariance and amplify magnetic fields during inflation, offering a mechanism for cosmic magnetization.

Findings

Magnetic fields of nanogauss strength can be generated on megaparsec scales.

The mechanism works for a wide range of Lorentz violation parameters.

The generated magnetic fields could explain observed cosmic magnetization.

Abstract

The Lorentz violating term in the photon sector of Standard Model Extension, $\mathcal{L}_K = -{$\frac14$} (k_F)_{\alpha \beta \mu \nu} F^{\alpha \beta} F^{\mu \nu}$ (here referred to as the Kosteleck\'{y} term), breaks conformal invariance of electromagnetism and enables a superadiabatic amplification of magnetic vacuum fluctuations during inflation. For a wide range of values of parameters defining Lorentz symmetry violation and inflation, the present-day magnetic field can have an intensity of order of nanogauss on megaparsec scales and then could explain the large-scale magnetization of the universe.