https://doi.org/10.1140/epje/i2018-11731-7
Regular Article
Effective temperature of active fluids and sheared soft glassy materials
Department of Chemical and Biological Physics, The Weizmann Institute of Science, 76100, Rehovot, Israel
* e-mail: nir.gov@weizmann.ac.il
Received:
30
March
2018
Accepted:
12
September
2018
Published online:
11
October
2018
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 a soft glassy material 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.
Key words: Topical issue: Flowing Matter, Problems and Applications
© EDP Sciences, SIF, Springer-Verlag GmbH Germany, part of Springer Nature, 2018