Method for Finding the Density Expansion of Transport Coefficients of Gases

This article presents a new method for finding the density expansion of certain transport coefficients of gases. Of these, the self-diffusion coefficient is the most important example. The method is to calculate the time-correlation function associated with the transport process. To lowest order in density, the results are identical with those found by Enskog's first-order perturbation solution of the Boltzmann equation. The first density correction requires the solution of a certain three-body problem. This problem is stated precisely, but is not solved.