Magnetogenesis from early structure formation due to Yukawa forces

TL;DR

This paper explores how Yukawa-mediated forces in the early universe can lead to structure formation and generate primordial magnetic fields, potentially seeding observed cosmic magnetic phenomena.

Contribution

It introduces a novel mechanism where energy from collapsing fermionic microhalos is converted into primordial magnetic fields during early structure formation.

Findings

Primordial magnetic fields can be generated from energy injection during microhalo collapse.

Estimated correlation scale and power spectrum of the generated magnetic fields.

Potential seed fields for observed astrophysical magnetic fields.

Abstract

Yukawa interactions can mediate relatively long-range attractive forces between fermions in the early universe. Such a globally attractive interaction creates an instability that can result in the growth of structure in the affected species even during the radiation dominated era. The formation and collapse of fermionic microhalos can create hot fireballs at the sites of the collapsing halos which inject energy into the cosmic plasma. In this paper we study a new phenomena which can take place in such models. We show that the injected energy can be partially converted into primordial magnetic fields and we estimate the correlation scale and the power spectrum of these fields. We show that they may be the seeds of the observed astrophysical magnetic fields.