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arXiv · 1605.00798

Additivity, density fluctuations, and nonequilibrium thermodynamics for active Brownian particles

Subhadip Chakraborti·Shradha Mishra·Punyabrata Pradhan
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Abstract

Using an additivity property, we study particle-number fluctuations in a system of interacting self-propelled particles, called active Brownian particles (ABPs), which consists of repulsive disks with random self-propulsion velocities. From a fluctuation-response relation - a direct consequence of additivity, we formulate a thermodynamic theory which captures the previously observed features of nonequilibrium phase transition in the ABPs from a homogeneous fluid phase to an inhomogeneous phase of coexisting gas and liquid. We substantiate the predictions of additivity by analytically calculating the subsystem particle-number distributions in the homogeneous fluid phase away from criticality where analytically obtained distributions are compatible with simulations in the ABPs.

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Subhadip Chakraborti, Shradha Mishra, Punyabrata Pradhan. 2016-05-03. Additivity, density fluctuations, and nonequilibrium thermodynamics for active Brownian particles. https://doi.org/10.1103/physreve.93.052606

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