Recent progress in fluctuation theorems and free energy recovery

TL;DR

This paper reviews recent advances in fluctuation theorems, emphasizing their experimental implications for free energy recovery in single molecule experiments and introducing a generalized Crooks relation for complex states.

Contribution

It highlights the importance of operational definitions and Galilean invariance in fluctuation relations and proposes a generalized Crooks relation for partially equilibrated states.

Findings

Operational definitions impact fluctuation relation applicability

Galilean invariance of fluctuation relations is experimentally testable

Generalized Crooks relation enables free energy recovery in complex states

Abstract

In this note we review recent progress about fluctuation relations and their applicability to free energy recovery in single molecule experiments. We underline the importance of the operational definition for the mechanical work and the non-invariance of fluctuation relations under Galilean transformations, both aspects currently amenable to experimental test. Finally we describe a generalization of the Crooks fluctuation relation useful to recover free energies of partially equilibrated states and thermodynamic branches.