  We perform a direct Monte Carlo simulation of the diffusion in a
multicomponent granular medium. We investigate the diffusion coefficients and
mean-squared displacements of granular particles in a polydisperse granular gas
in a homogeneous cooling state containing an arbitrary number of species of
different sizes and masses using both models of constant and time-dependent
restitution coefficients. In our study, we used a powerful low-rank algorithm
that allows for efficient simulation of highly polydisperse granular systems.
Mean square displacements in Monte Carlo simulations are in good agreement with
theoretical predictions.
