Correlated curvature perturbations and magnetogenesis from the GUT gauge bosons

TL;DR

This paper proposes a mechanism during GUT-scale hybrid inflation where gauge bosons generate curvature perturbations and primordial magnetic fields, potentially explaining galactic magnetism through a vector curvaton approach.

Contribution

It introduces a novel scenario where GUT gauge bosons produce correlated curvature and magnetic perturbations via the vector curvaton mechanism.

Findings

Gauge bosons can generate observable curvature perturbations.

Primordial magnetic fields of galactic strength can be produced.

The mechanism links GUT physics to cosmological magnetic fields.

Abstract

In the context of hybrid inflation at the scale of grand unification, it is shown that, if (some of) the gauge bosons of the unbroken grand unified group obtain a flat superhorizon spectrum of perturbations from inflation they can affect or even generate both the observed curvature perturbation and simultaneously produce a sizable primordial magnetic field capable of explaining galactic magnetism. The mechanism employs the vector curvaton idea for a supermassive grand unified gauge boson after the breaking of grand unification.