Chiral Alfv\'en Wave in Anomalous Hydrodynamics

TL;DR

This paper introduces a novel gapless collective excitation called the chiral Alfvén wave in high-temperature chiral plasmas, driven by chiral effects and gravitational anomalies, with potential relevance to physical systems.

Contribution

It identifies and characterizes a new type of transverse wave in chiral hydrodynamics, expanding understanding of collective excitations influenced by anomalies.

Findings

Discovery of a new gapless wave in chiral plasmas.

Wave velocity proportional to gravitational anomaly coefficient.

Presence of the wave even in incompressible fluids.

Abstract

We study the hydrodynamic regime of chiral plasmas at high temperature. We find a new type of gapless collective excitation induced by chiral effects in an external magnetic field. This is a transverse wave, and it is present even in incompressible fluids, unlike the chiral magnetic and chiral vortical waves. The velocity is proportional to the coefficient of the gravitational anomaly. We briefly discuss the possible relevance of this "chiral Alfv\'en wave" in physical systems.