Elasticity typically refers to a material's ability to store energy, whereas viscosity refers to a
material's tendency to dissipate it. In this review, we discuss fluids and solids for which this is …

There has been a surge of interest in effective non-Lorentzian theories of excitations with
restricted mobility, known as fractons. Examples include defects in elastic materials, vortex …

We consistently couple simple continuum field theories with fracton excitations to curved
spacetime backgrounds. We consider homogeneous and isotropic fracton field theories, with …

We introduce a new kind of foliated quantum field theory (FQFT) of gapped fracton orders in
the continuum. FQFT is defined on a manifold with a layered structure given by one or more …

The (2+ 1)-dimensional continuum Lifshitz theory of a free compact scalar field plays a
prominent role in a variety of quantum systems in condensed matter physics and high …

We study p-string condensation mechanisms for fracton phases from the viewpoint of higher-
form symmetry, focusing on the examples of the X-cube model and the rank-two symmetric …

Low-energy dynamics of many-body fracton excitations necessary to describe topological
defects should be governed by a novel type of hydrodynamic theory. We use a Poisson …

We classify one-dimensional symmetry-protected topological (SPT) phases protected by
dipole symmetries. A dipole symmetry comprises two sets of symmetry generators: charge …

Crystallography typically studies collections of point particles whose interaction forces are
the gradient of a potential. Lifting this assumption generically gives rise in the continuum …

Dipole-conserving fluids serve as examples of kinematically constrained systems that can
be understood on the basis of symmetry. They are known to display various exotic features …