On the second fluctuation--dissipation theorem for nonequilibrium baths
Statistical Mechanics
2015-06-17 v1
Abstract
Baths produce friction and random forcing on particles suspended in them. The relation between noise and friction in (generalized) Langevin equations is usually referred to as the second fluctuation-dissipation theorem. We show what is the proper nonequilibrium extension, to be applied when the environment is itself active and driven. In particular we determine the effective Langevin dynamics of a probe from integrating out a steady nonequilibrium environment. The friction kernel picks up a frenetic contribution, i.e., involving the environment's dynamical activity, responsible for the breaking of the standard Einstein relation.
Cite
@article{arxiv.1309.3160,
title = {On the second fluctuation--dissipation theorem for nonequilibrium baths},
author = {Christian Maes},
journal= {arXiv preprint arXiv:1309.3160},
year = {2015}
}