Fluctuating Motion in an Active Environment
Christian Maes
Abstract
We derive the fluctuation dynamics of a probe in weak coupling with a living medium, modeled as particles undergoing an active Ornstein-Uhlenbeck dynamics. Nondissipative corrections to the fluctuation-dissipation relation are written out explicitly in terms of time correlations in the active medium. A first term changes the inertial mass of the probe as a consequence of the persistence of the active medium. A second correction modifies the friction kernel. The resulting generalized Langevin equation benchmarks the motion induced on probes immersed in active versus passive media. The derivation uses nonequilibrium response theory.
Topics & Concepts
PhysicsDynamics (music)DissipationActive matterNon-equilibrium thermodynamicsInertial frame of referenceClassical mechanicsLangevin equationTerm (time)Momentum (technical analysis)Motion (physics)Statistical physicsQuantum mechanicsAcousticsEconomicsCell biologyBiologyFinanceMicro and Nano RoboticsAdvanced Thermodynamics and Statistical Mechanicsstochastic dynamics and bifurcation