Marginal and Conditional Second Laws of Thermodynamics

TL;DR

This paper introduces local second laws for strongly coupled bipartite systems by partitioning entropy production, using causal intervention to identify feedback contributions, thus extending thermodynamics beyond weak coupling assumptions.

Contribution

It presents a novel framework for defining local second laws in strongly coupled systems using entropy partitioning and causal intervention techniques.

Findings

Partitioned entropy production components clarify feedback effects.

Local second laws valid without weak coupling assumptions.

Central thermodynamic relations derived succinctly.

Abstract

We consider the entropy production of a strongly coupled bipartite system. The total entropy production can be partitioned into various components, which we use to define local versions of the Second Law that are valid without the usual idealization of weak coupling. The key insight is that causal intervention offers a way to identify those parts of the entropy production that result from feedback between the sub-systems. From this the central relations describing the thermodynamics of strongly coupled systems follow in a few lines.