Two-field cosmological models and large-scale cosmic magnetic fields

TL;DR

This paper explores two cosmological models with scalar and phantom fields, demonstrating how magnetic field amplification effects can distinguish between models with identical universe evolution.

Contribution

It introduces two toy models with different field interactions that produce the same cosmic evolution but differ in magnetic field amplification effects.

Findings

Magnetic field amplification varies between models.

Presence of pseudoscalar field breaks conformal invariance.

Amplification effects can differentiate cosmological models.

Abstract

We consider two different toy cosmological models based on two fields (one normal scalar and one phantom) realizing the same evolution of the Bang-to-Rip type. One of the fields (pseudoscalar) interacts with the magnetic field breaking the conformal invariance of the latter. The effects of the amplification of cosmic magnetic fields are studied and it is shown that the presence of such effects can discriminate between different cosmological models realizing the same global evolution of the universe.