Lorentz Symmetry Violation and Galactic Magnetism

TL;DR

This paper explores how Lorentz-violating electrodynamics during inflation can generate primordial magnetic fields that evolve into the galactic magnetic fields observed today, through a helical field mechanism and turbulence effects.

Contribution

It introduces a Lorentz-violating model with a Chern-Simons term that produces maximally helical magnetic fields capable of explaining galactic magnetism.

Findings

Generated magnetic fields are maximally helical.

Inverse cascade amplifies the magnetic field during plasma turbulence.

Resulting fields match observed galactic magnetic field properties.

Abstract

We analyze the generation of primordial magnetic fields during de Sitter inflation in a Lorentz-violating theory of Electrodynamics containing a Chern-Simons term which couples the photon to an external four-vector. We find that, for appropriate magnitude of the four-vector, the generated field is maximally helical and, through an inverse cascade caused by turbulence of primeval plasma, reaches at the time of protogalactic collapse an intensity and correlation length such as to directly explain galactic magnetism.