Chiral anomaly and dynamos from inhomogeneous chemical potential fluctuations

TL;DR

This paper demonstrates through simulations that inhomogeneous chemical potential fluctuations in relativistic plasmas can trigger a chiral dynamo instability, leading to magnetic turbulence and large-scale magnetic fields via the magnetic alpha effect.

Contribution

It introduces a novel mechanism where spatial chemical potential fluctuations induce chiral dynamo effects in relativistic plasmas, supported by direct numerical simulations.

Findings

Chemical potential fluctuations can cause chiral dynamo instability.

The instability leads to magnetically driven turbulence.

Large-scale magnetic fields can be generated through the magnetic alpha effect.

Abstract

In the standard model of particle physics, the chiral anomaly can occur in relativistic plasmas and plays a role in the early Universe, protoneutron stars, heavy-ion collisions, and quantum materials. It gives rise to a magnetic instability if the number densities of left- and right-handed electrically charged fermions are unequal. Using direct numerical simulations, we show this can result just from spatial fluctuations of the chemical potential, causing a chiral dynamo instability, magnetically driven turbulence, and ultimately a large-scale magnetic field through the magnetic alpha effect.