Magnetogenesis in non-local models during inflation

TL;DR

This paper investigates whether non-local modifications to electromagnetic theory during inflation can generate primordial magnetic fields, finding that such non-local effects alone do not produce magnetic fields without inflaton coupling, and can inhibit their generation if coupled.

Contribution

It introduces a non-local form factor in Maxwell's equations during inflation and analyzes its impact on magnetic field generation, revealing inhibitory effects when coupled with the inflaton.

Findings

Non-local form factors do not generate magnetic fields without inflaton interaction.

Coupling with the inflaton inhibits magnetic field generation compared to local models.

Conformal symmetry breaking alone is insufficient for primordial magnetogenesis.

Abstract

The generation of magnetic fields during inflation in an electromagnetic model with a non-local form factor in Maxwell`s action is studied. The equations of motion for the electromagnetic field are derived and solved. It is found that the conformal symmetry breaking due to the non-local form factor does not lead to the generation of magnetic fields during inflation in the absence of interaction with the inflaton field. If such a coupling takes place, then the presence of the form factor inhibits the generation of primordial magnetic fields compared to the case where the non-local form factor is absent.