Origins and diagnostics of the nonequilibrium character of active systems

Lokrshi Prawar Dadhichi; Ananyo Maitra; Sriram Ramaswamy

doi:10.1088/1742-5468/aae852

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arXiv · 1808.08997

Origins and diagnostics of the nonequilibrium character of active systems

Lokrshi Prawar Dadhichi·Ananyo Maitra·Sriram Ramaswamy

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Abstract

We present in detail a Langevin formalism for constructing stochastic dynamical equations for active-matter systems coupled to a thermal bath. We apply the formalism to clarify issues of principle regarding the sources and signatures of nonequilibrium behaviour in a variety of polar and apolar single-particle systems and polar flocks. We show that distance from thermal equilibrium depends on how time-reversal is implemented and hence on the reference equilibrium state. We predict characteristic forms for the frequency-resolved entropy production for an active polar particle in a harmonic potential, which should be testable in experiments.

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Lokrshi Prawar Dadhichi, Ananyo Maitra, Sriram Ramaswamy. 2018-08-27. Origins and diagnostics of the nonequilibrium character of active systems. https://doi.org/10.1088/1742-5468/aae852

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