Free energy surfaces from nonequilibrium processes without work measurement

TL;DR

This paper introduces a novel method to estimate equilibrium free energies from nonequilibrium processes that do not involve work measurement, expanding the toolkit for statistical mechanics analyses.

Contribution

It proposes a simple strategy for estimating free energies from clamp-and-release processes without work measurement, demonstrated through simulations and analysis of single-molecule experiments.

Findings

Effective free energy estimation without work measurement.

Applicable to tethered single-molecule experiments.

Validated through numerical simulations.

Abstract

Recent developments in statistical mechanics have allowed the estimation of equilibrium free energies from the statistics of work measurements during processes that drive the system out of equilibrium. Here a different class of processes is considered, wherein the system is prepared and released from a nonequilibrium state, and no external work is involved during its observation. For such ``clamp-and-release'' processes, a simple strategy for the estimation of equilibrium free energies is offered. The method is illustrated with numerical simulations, and analyzed in the context of tethered single-molecule experiments.