Granular gases: dynamics and collective effects

TL;DR

This paper reviews the complex behaviors of granular gases, highlighting phenomena like Maxwell Demon effects, modified Fourier's law, and non-Gaussian velocity distributions caused by dissipative collisions.

Contribution

It provides a non-technical overview of key collective effects and phenomena in granular gases, emphasizing their differences from equilibrium gases.

Findings

Demonstration of Maxwell Demon-like effects

Modification of Fourier's law in granular gases

Presence of non-Gaussian velocity distributions

Abstract

We present a biased review of some of the most "spectacular" effects appearing in the dynamics of granular gases where the dissipative nature of the collisions leads to a rich phenomenology, exhibiting striking differences with equilibrium gases. Among these differences, the focus here is on the illustrative examples of ``Maxwell Demon''-like experiment, modification of Fourier's law, non-equipartition of energy and non-Gaussianity of the velocity distributions. The presentation remains as non technical as possible.