Infinite families of fracton fluids with momentum conservation

TL;DR

This paper introduces new classes of fracton hydrodynamics with momentum conservation, exploring their properties, instabilities, and potential non-equilibrium fixed points across various dimensions.

Contribution

It constructs infinite families of universality classes of fracton fluids with momentum conservation, including models with multipole conservation and subsystem symmetry, and analyzes their stability and fixed points.

Findings

New universality classes of fracton hydrodynamics identified.

Explicit microscopic models for 1D multipole-conserving systems provided.

All classes exhibit instabilities leading to non-equilibrium fixed points.

Abstract

We construct infinite families of new universality classes of fracton hydrodynamics with momentum conservation, both with multipole conservation laws and/or subsystem symmetry. We explore the effects of broken inversion and/or time-reversal symmetry at the ideal fluid level, along with momentum relaxation. In the case of one-dimensional multipole-conserving models, we write down explicit microscopic Hamiltonian systems realizing these new universality classes. All of these hydrodynamic universality classes exhibit instabilities and will flow to new non-equilibrium fixed points. Such fixed points are predicted to exist in arbitrarily large spatial dimensions.