2021/10/01 by Feng, Mengkai, Hou, Zhonghuai
#FOS: Physical sciences #Soft Condensed Matter (cond-mat.soft) #Statistical Mechanics (cond-mat.stat-mech)
paper · doi:10.48550/arxiv.2110.00279
We develop a theoretical framework to study the effective dynamics of a tracer immersed in a nonequilibrium bath consisting of active particles. By using a mean-field approximation and extending the linearized Dean equation to nonequilibrium environment, we derive a generalized Langevin equation for the tracer particle, wherein colored noise terms and a memory kernel reflect the roles of interactions between tracer and bath particles as well as activity of the bath. In particular, we obtain a self-consistent equation to calculate the long time diffusion coefficient and mobility of tracer, finding that they both increase non-linearly with bath activity, in good consistents with direct simulation results.