Active Brownian particles: Entropy production and fluctuation-response

TL;DR

This paper investigates entropy production and fluctuation-response relations in active Brownian particles modeled by the Rayleigh-Helmholtz framework, revealing detailed fluctuation theorems and modified fluctuation-dissipation relations through simulations.

Contribution

It demonstrates the validity of fluctuation theorems and modifies fluctuation-dissipation relations for active particles with non-linear velocity-dependent forces.

Findings

Probability distributions obey detailed fluctuation theorem.

Steady state response function follows a modified fluctuation-dissipation relation.

Entropy production distributions are obtained via molecular dynamics simulations.

Abstract

Within the Rayleigh-Helmholtz model of active Brownian particles activity is due to a non-linear velocity dependent force. In the presence of an external trapping potential or a constant force, the steady state of the system breaks detailed balance producing a net entropy. Using molecular dynamics simulations, we obtain the probability distributions of entropy production in these steady states. The distribution functions obey detailed fluctuation theorem for entropy production. Using simulation results, we further show that the steady state response function obeys a modified fluctuation-dissipation relation.