Quantum macrostatistical picture of nonequilibrium steady states

TL;DR

This paper develops a quantum macrostatistical framework to analyze nonequilibrium steady states, demonstrating that hydrodynamical observables follow a generalized Onsager-Machlup process and exhibit long-range spatial correlations.

Contribution

It introduces a quantum macrostatistical approach to describe nonequilibrium steady states, extending Onsager's regression hypothesis and revealing long-range correlations.

Findings

Hydrodynamical observables follow a generalized Onsager-Machlup process.

Spatial correlations are generally of long range.

Results rely on assumptions of local equilibrium and chaoticity.

Abstract

We employ a quantum macrostatistical treatment of irreversible processes to prove that, in nonequilibrium steady states, (a) the hydrodynamical observables execute a generalised Onsager-Machlup process and (b) the spatial correlations of these observables are generically of long range. The key assumptions behind these results are a nonequilibrium version of Onsager's regression hypothesis, together with certain hypotheses of chaoticity and local equilibrium for hydrodynamical fluctuations.