Diffusion in a Lattice Gas Automaton

Abstract

A two-dimensional lattice gas automaton with two species ("colors") of particles is studied to determine the behavior of its diffusion coefficient. The diffusion coefficient is measured by establishing a color-density gradient across the width of a rectangular channel and observing the resulting flux of particles of the two species. Accurate estimates of the diffusion coefficient as a function of system size are obtained and are found to exhibit the logarithmic divergence expected for transport coefficients in two dimensions.