Heat fluctuations and fluctuation theorems in the case of multiple reservoirs

TL;DR

This paper investigates heat fluctuations in systems connected to multiple reservoirs, establishing a fundamental symmetry that generalizes fluctuation theorems and influences heat distribution tails, with implications for nonequilibrium thermodynamics.

Contribution

It introduces a fundamental symmetry for heat transfer distributions in multi-reservoir systems, generalizing fluctuation theorems and deriving new relations including time-dependent protocols.

Findings

Symmetry in joint probability distribution of heat and system states.

Generalization of the asymptotic fluctuation theorem for large deviations.

Derivation of an exact fluctuation theorem valid at all times.

Abstract

We consider heat fluctuations and fluctuation theorems for systems driven by multiple reservoirs. We establish a fundamental symmetry obeyed by the joint probability distribution for the heat transfers and system coordinates. The symmetry leads to a generalisation of the asymptotic fluctuation theorem for large deviations at large times. As a result the presence of multiple reservoirs influence the tails in the heat distribution. The symmetry, moreover, allows for a simple derivation of a recent exact fluctuation theorem valid at all times. Including a time dependent work protocol we also present a derivation of the integral fluctuation theorem.