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arXiv · 2105.13365

Breakdown of hydrodynamics below four dimensions in a fracton fluid

Abstract

We present the nonlinear fluctuating hydrodynamics which governs the late time dynamics of a chaotic many-body system with simultaneous charge/mass, dipole/center of mass, and momentum conservation. This hydrodynamic effective theory is unstable below four spatial dimensions: dipole-conserving fluids at rest become unstable to fluctuations, and are governed not by hydrodynamics, but by a fractonic generalization of the Kardar-Parisi-Zhang universality class. We numerically simulate many-body classical dynamics in one-dimensional models with dipole and momentum conservation, and find evidence for a breakdown of hydrodynamics, along with a new universality class of undriven yet non-equilbrium dynamics.

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Paolo Glorioso, Jinkang Guo, Joaquin F. Rodriguez-Nieva, Andrew Lucas. 2021-05-27. Breakdown of hydrodynamics below four dimensions in a fracton fluid. https://doi.org/10.1038/s41567-022-01631-x

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