Equilibrium free energy differences from nonequilibrium measurements: a master equation approach

TL;DR

This paper establishes a master equation-based identity that allows calculating equilibrium free energy differences from nonequilibrium work measurements, supported by examples and numerical illustrations.

Contribution

It introduces a master equation approach to derive free energy differences from nonequilibrium work data, extending previous results.

Findings

Identity connecting work measurements to free energy differences

Numerical examples demonstrating the approach

Applicability to various systems

Abstract

It has recently been shown that the Helmholtz free energy difference between two equilibrium configurations of a system may be obtained from an ensemble of finite-time (nonequilibrium) measurements of the work performed in switching an external parameter of the system. Here this result is established, as an identity, within the master equation formalism. Examples are discussed and numerical illustrations provided.