Dynamical processes in hard-sphere fluids

Abstract

For a classical fluid of hard spheres the nine hydrodynamic time-correlation functions between the microscopic density, longitudinal velocity, and temperature are calculated theoretically on the basis of the revised Enskog theory for all densities and wave numbers. It appears that a simplified description of these correlation functions is possible for small wave numbers in terms of extended hydrodynamic modes and for large wave numbers in terms of free streaming and a single binary collision.