Comments on Violations of the Second Law

TL;DR

This paper critically examines claims of second law violations, arguing that the assertions made in prior work are incorrect and clarifying misunderstandings about entropy production and fluctuation theorems.

Contribution

It provides a critical analysis refuting previous claims of second law violations and clarifies misconceptions about entropy and fluctuation theorems.

Findings

Claims of second law violations are incorrect

Entropy production is positive for large systems over long times

Fluctuation theorem does not imply violations of the second law

Abstract

The authors of Ref. [1] claim to have experimental verification of violations of the second law of thermodynamics based on the assertions: (i) "for large systems and over long times the entropy production rate is necessarily positive"; (ii) Loschmidt's paradox interpreted as indicating that entropy production can be both positive and negative; (iii) and violations of the second law for small systems over short time scales predicted by the fluctuation theorem FT [2]. Neither the claim nor the assertions are correct.