Shear viscoelasticity in anisotropic holographic axion model

TL;DR

This paper explores how broken symmetries in a holographic axion model affect shear elasticity and viscosity, revealing that spontaneous symmetry breaking enhances shear elasticity but suppresses shear viscosity, contrasting with previous superfluid studies.

Contribution

It provides new insights into the effects of broken translational and rotational symmetries on shear viscoelastic properties in a holographic framework.

Findings

Broken translations and anisotropy increase shear elasticity.

Broken symmetries suppress shear viscosity.

Contrast with superfluid behavior where viscosity is enhanced.

Abstract

In this work, we investigate the shear elasticity and the shear viscosity in a simple holographic axion model with broken translational symmetry and rotational symmetry in space via the perturbation computation. We find that, in the case of spontaneous symmetry breaking, the broken translations and anisotropy both enhance the shear elasticity of the system. While in all cases, the broken symmetries introduce a double suppression on the shear viscosity, which is in contrast to the result from the study of the p-wave holographic superfluid where the shear viscosity is enhanced when the rotational symmetry is broken spontaneously.