Fractonic solids

TL;DR

This paper introduces a new symmetry principle for fractonic solids that restricts fracton mobility relative to physical materials, allowing gauge-invariant momentum, compatibility with boost symmetry, and coupling to gravity.

Contribution

It proposes a novel symmetry framework for fractons in physical solids, extending their theoretical understanding and potential real-world applications.

Findings

Fractonic solids admit gauge-invariant momentum density.

They are compatible with boost symmetry.

A holographic model for fractonic solids is proposed.

Abstract

Fractons are exotic quasiparticles whose mobility in space is restricted by symmetries. In potential real-world realisations, fractons are likely lodged to a physical material rather than absolute space. Motivated by this, we propose and explore a new symmetry principle that restricts the motion of fractons relative to a physical solid. Unlike models with restricted mobility in absolute space, these fractonic solids admit gauge-invariant momentum density, are compatible with boost symmetry, and can consistently be coupled to gravity. We also propose a holographic model for fractonic solids.