Structure of the H Function for a Hard-Sphere Gas

Abstract

We consider, for a spatially uniform hard-sphere gas, the generalization of the connection between the H function and the thermodynamic entropy to that limit where gas imperfections are taken into account through the first virial correction term. Our choice of a generalized H function is based on the expansion of the canonical entropy density given by Nettleton and Green. We show that this choice allows us to give a physical significance to the condition that Boltzmann's H function be convex as a function of time.