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arXiv · 2405.02283

Thermodynamic constraints and exact scaling exponents of flocking matter

Andrea Amoretti·Daniel K. Brattan·Luca Martinoia
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Abstract

We use advances in the formalism of boost agnostic passive fluids to constrain transport in polar active fluids, which are subsequently described by the Toner-Tu equations. Acknowledging that the system fundamentally breaks boost symmetry we compel what were previously entirely phenomenological parameters in the Toner-Tu model to satisfy precise relationships among themselves. Consequently, we propose a thermodynamic argument to determine the exact scalings of the transport coefficients under dynamical renormalisation group flow. These scalings perfectly agree with the results of recent state-of-the-art numerical simulation and experiments

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Andrea Amoretti, Daniel K. Brattan, Luca Martinoia. 2024-05-03. Thermodynamic constraints and exact scaling exponents of flocking matter. https://doi.org/10.1103/physreve.110.054108

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