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Communication: Green-Kubo approach to the average swim speed in active Brownian systems
1Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland.
Abstract:
We develop an exact Green-Kubo formula relating nonequilibrium averages in systems of interacting active Brownian particles to equilibrium time-correlation functions. The method is applied to calculate the density-dependent average swim speed, which is a key quantity entering coarse grained theories of active matter. The average swim speed is determined by integrating the equilibrium autocorrelation function of the interaction force acting on a tagged particle. Analytical results are validated using Brownian dynamics simulations.
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