Dissipative Charged Fluid in a Magnetic Field

TL;DR

This paper investigates how an external magnetic field influences collective excitations and transport properties in a dissipative charged fluid at zero chemical potential, revealing additional hydrodynamic modes and altered correlations.

Contribution

It introduces the analysis of magnetic field effects on collective modes and derives new Kubo formulas for transport coefficients in such fluids.

Findings

Presence of five hydrodynamic modes with magnetic field

Magnetic field splits degeneracy between shear modes

Charge-energy correlation persists at zero chemical potential

Abstract

We study the collective excitations in a dissipative charged fluid at zero chemical potential when an external magnetic field is present. While in the absence of magnetic field, four collective excitations appear in the fluid, we find five hydrodynamic modes in presence of magnetic field. This implies that the magnetic field splits the degeneracy between the transverse shear modes. Using linear response theory, we then compute the retarded response functions. In particular, it turns out that the correlation between charge and the energy fluctuations will no longer vanish, even at zero chemical potential. By use of the response functions, we also derive the relevant Kubo formulas for the transport coefficients.