Effective temperature of active fluids and sheared granular matter
Abstract
The dynamics within active fluids, driven by internal activity of the self-propelled particles, is a subject of intense study in non-equilibrium physics. These systems have been explored using simulations, where the motion of a passive tracer particle is followed. Similar studies have been carried out for passive granular matter that is driven by shearing its boundaries. In both types of systems the non-equilibrium motion have been quantified by defining a set of "effective temperatures", using both the tracer particle kinetic energy and the fluctuation-dissipation relation. We demonstrate that these effective temperatures extracted from the many-body simulations fit analytical expressions that are obtained for a single active particle inside a visco-elastic fluid. This result provides testable predictions and suggests a unified description for the dynamics inside active systems.
Cite
@article{arxiv.1804.00219,
title = {Effective temperature of active fluids and sheared granular matter},
author = {Saroj Kumar Nandi and Nir S. Gov},
journal= {arXiv preprint arXiv:1804.00219},
year = {2018}
}