A Local Fluctuation Theorem

TL;DR

This paper derives a Local Fluctuation Theorem (LFT) applicable to finite nonequilibrium systems and validates it through molecular dynamics simulations of planar Poiseuille flow, extending the understanding of thermodynamic fluctuations.

Contribution

The paper introduces a Local Fluctuation Theorem (LFT) and demonstrates its validity in specific fluid flow simulations, providing a new perspective on nonequilibrium thermodynamics.

Findings

LFT derived for finite systems and times

Simulation results support LFT in Poiseuille flow

Extends fluctuation theorem applicability to local scales

Abstract

The Fluctuation Theorem (FT) gives an analytic expression for the probability, in a nonequilibrium system of finite size observed for a finite time, that the dissipative flux will flow in the reverse direction to that required by the Second Law of Thermodynamics. In the present letter a Local version of the Fluctuation Theorem (LFT), is derived. We find that in the case of planar Poiseuille flow of a Newtonian fluid between thermostatted walls, non-equilibrium molecular dynamics simulation results support LFT.