Dynamics of fluid dynamics fluctuations by particle simulations

Space-time correlation function of density and pressure for equilibrium Argon gas in the hydrodynamic regime have been calculated by the DSMC particle simulation method. The results agree well with the predictions of a linear hydrodynamic theory and look promising in view of the possible application of the method to the study of systems for which a theoretical description is more problematic. It is the case of the equilibrium fluctuations in molecular gases, fluctuations in the kinetic regime and fluctuations in non-equilibrium conditions.