Lorentz-violating inflationary magnetogenesis

TL;DR

This paper explores how Lorentz-violating couplings during inflation can generate primordial magnetic fields compatible with observations, avoiding common theoretical problems and explaining cosmic magnetic fields.

Contribution

It introduces a Lorentz-violating coupling model that successfully produces magnetic fields during inflation without the usual strong-coupling or backreaction issues.

Findings

Magnetic fields generated are consistent with CMB observations.

The model evades strong-coupling and backreaction problems.

Primordial spectra of curvature perturbations match observational data.

Abstract

A non-conformally invariant coupling between the inflaton and the photon in the minimal Lorentz-violating standard model extension is analyzed. For specific forms of the Lorentz-violating background tensor, the strong-coupling and backreaction problems of magnetogenesis in de Sitter inflation with scale $\sim 10^{16}$GeV are evaded, the electromagnetic-induced primordial spectra of (Gaussian and non-Gaussian) scalar and tensor curvature perturbations are compatible with cosmic microwave background observations, and the inflation-produced magnetic field directly accounts for cosmic magnetic fields.