Heat conduction and Fourier's law by consecutive local mixing and thermalization

TL;DR

This paper investigates heat conduction through a new multi-step local thermalization mechanism caused by binary collisions, leading to Fourier's law, with implications for multi-phase materials like aerogels.

Contribution

It introduces a first-principles model demonstrating a novel local thermalization process resulting in Fourier's law.

Findings

Local thermalization occurs via binary collisions.

Fourier's law emerges from the multi-step thermalization mechanism.

The mechanism's relevance to multi-phase materials like aerogels.

Abstract

We present a first-principles study of heat conduction in a class of models which exhibit a new multi-step local thermalization mechanism which gives rise to Fourier's law. Local thermalization in our models occurs as the result of binary collisions among locally confined gas particles. We explore the conditions under which relaxation to local equilibrium, which involves no energy exchange, takes place on time scales shorter than that of the binary collisions which induce local thermalization. The role of this mechanism in multi-phase material systems such as aerogels is discussed.