How statistical forces depend on thermodynamics and kinetics of driven media

TL;DR

This paper investigates how statistical forces on a probe in nonequilibrium media relate to thermodynamic and kinetic properties, revealing nonadditivity and constraints on nonequilibrium thermodynamics.

Contribution

It demonstrates the dependence of statistical forces on nonequilibrium thermodynamics and kinetics, highlighting nonadditivity and the role of reaction pathways.

Findings

In the linear regime, work on the probe equals the excess work for medium relaxation.

Statistical forces reveal information about nonequilibrium reactivity changes.

For nonequilibrium media, statistical forces are generally nonadditive.

Abstract

We study the statistical force of a nonequilibrium environment on a quasi-static probe. In the linear regime the isothermal work on the probe equals the excess work for the medium to relax to its new steady condition with displaced probe. Also the relative importance of reaction paths can be measured via statistical forces, and from second order onwards the force on the probe reveals information about nonequilibrium changes in the reactivity of the medium. We also show that statistical forces for nonequilibrium media are generally nonadditive, in contrast with the equilibrium situation. Both the presence of non-thermodynamic corrections to the forces and their nonadditivity put serious constraints on any formulation of nonequilibrium steady state thermodynamics.