On the Violations of Local Equilibrium and Linear Response

TL;DR

This paper investigates how local equilibrium and linear response assumptions fail in classical lattice models far from equilibrium, revealing non-local effects and size-dependent behaviors in heat transport.

Contribution

It provides a detailed analysis of the simultaneous breakdown of local equilibrium and linear response in lattice models, highlighting non-local corrections and size effects.

Findings

Linear response and local equilibrium break down simultaneously.

Non-local corrections develop in the steady state.

Observables show non-trivial size dependence.

Abstract

We study how local equilibrium, and linear response predictions of transport coefficients are violated as systems move far from equilibrium. This is done by studying heat flow in classical lattice models with and without bulk transport behavior, in 1--3 dimensions. We see that linear response and local equilibrium assumptions break down at the same rate. The equation of state is also found to develop non-local corrections in the steady state. We quantify the breakdown through the analysis of both microscopic and macroscopic observables, which are found to display non-trivial size dependence.