Far-from-Equilibrium Distribution from Near-Steady-State Work Fluctuations
arXiv:1501.00238 · doi:10.1103/PhysRevE.92.052120
Abstract
A longstanding goal of nonequilibrium statistical mechanics has been to extend the conceptual power of the Boltzmann distribution to driven systems. We report some new progress towards this goal. Instead of writing the nonequilibrium steady-state distribution in terms of perturbations around thermal equilibrium, we start from the linearized driven dynamics of observables about their stable fixed point, and expand in the strength of the nonlinearities encountered during typical fluctuations away from the fixed point. The first terms in this expansion retain the simplicity of known expansions about equilibrium, but can correctly describe the statistics of a certain class of systems even under strong driving. We illustrate this approach by comparison with a numerical simulation of a sheared Brownian colloid, where we find that the first two terms in our expansion are sufficient to account for the shear thinning behavior at high shear rates.
17 pages, 5 figures
References in corpus (7)
- Macroscopic fluctuation theory
- Nonlinear rheology of colloidal dispersions
- Extended Fluctuation-Dissipation Theorem for Soft Matter in Stationary Flow
- Representation of nonequilibrium steady states in large mechanical systems
- Fluctuation dissipation relations in stationary states of interacting Brownian particles under shear
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- Effective temperatures of a driven, strongly anisotropic Brownian system