Tightening the thermodynamic uncertainty relations with null-entropy events: What we learn when nothing happens

TL;DR

This paper enhances thermodynamic uncertainty relations by incorporating null-entropy events, providing tighter bounds on fluctuations in microscopic thermodynamic processes, validated through a qudit SWAP engine example.

Contribution

It introduces a novel approach that includes null-entropy events to tighten bounds on thermodynamic fluctuations, advancing the understanding of microscopic thermodynamics.

Findings

Null-entropy events impose additional constraints on fluctuations.

Tighter bounds on thermodynamic uncertainty relations are derived.

Validation with a qudit SWAP engine confirms the theoretical improvements.

Abstract

Fluctuation theorems establish that thermodynamic processes at the microscale can occasionally result in negative entropy production. At the microscale, another distinct possibility becomes more likely: processes in which no entropy is produced overall. In this work, we explore the constraints imposed by such null-entropy events on the fluctuations of thermodynamic currents. By incorporating the probability of null-entropy events, we obtain tighter bounds on finite-time thermodynamic uncertainty relations derived from fluctuation theorems. We validate this framework using an example of a qudit SWAP engine.