Gravitational Anomaly and Transport

TL;DR

This paper investigates how gravitational anomalies influence transport phenomena in relativistic fluids, revealing that they induce vortical effects even in uncharged fluids through calculations of Kubo formulas.

Contribution

It provides a weak-coupling calculation of the anomalous vortical conductivity, demonstrating the role of gravitational anomalies in transport phenomena.

Findings

Gravitational anomalies contribute to vortical conductivity.

Anomalous vortical effect occurs in uncharged fluids.

Kubo formulas are used to evaluate transport coefficients.

Abstract

Quantum anomalies give rise to new transport phenomena. In particular a magnetic field can induce an anomalous current via the chiral magnetic effect and a vortex in the relativistic fluid can also induce a current via the chiral vortical effect. The related transport coefficients can be calculated via Kubo formulas. We evaluate the Kubo formula for the anomalous vortical conductivity at weak coupling and show that it receives contributions proportional to the gravitational anomaly coefficient. The gravitational anomaly gives rise to an anomalous vortical effect even for an uncharged fluid.