Journal of Statistical Physics, Vol. 62, Nos. 3/4, 1991. p. 737-757.
The diffusion process of point particles moving on regular triangular and random lattices, randomly occupied with stationary scatterers (a Lorentz lattice gas cellular automaton), is studied, for strictly deterministic scattering rules, as a function of the concentration of the scatterers. In addition to the normal and various kinds "of retarded diffusion found before on the regular square lattice, straight-line propagation through the scatterers is observed.