Cosmological magnetic fields in turbulent matter

TL;DR

This paper investigates how magnetic fields evolve in turbulent early Universe plasma, highlighting the role of the chiral magnetic effect in amplifying magnetic fields through a new kinetic equation framework.

Contribution

It introduces a novel kinetic equation system for magnetic helicity, magnetic energy, and chiral imbalance, explicitly modeling turbulence effects in early Universe conditions.

Findings

Magnetic field amplification is driven solely by the chiral magnetic effect.

Turbulence influences the evolution and amplification of primordial magnetic fields.

Numerical solutions show different outcomes based on initial seed magnetic fields.

Abstract

We study the evolution of magnetic fields in turbulent hot plasma of the early Universe accounting for the chiral magnetic effect. The magnetohydrodynamic turbulence is modeled by replacing the matter velocity in the advection term in the Faraday equation with the Lorentz force. The system of the kinetic equations for the spectra of the densities of the magnetic helicity and the magnetic energy, as well as for the chiral imbalance, is derived. The amplification of the magnetic field is shown to result from the presence of the chiral magnetic effect solely. The system of the kinetic equations is solved numerically in primordial plasma after the electroweak phase transition. The influence of the matter turbulence on the magnetic field evolution is examined for different seed magnetic fields.