Kinetics of two-dimensional ballistic annihilation: A multiparticle lattice gas study

In many equilibrium or nonequilibrium statistical physics problems, fluctua tions play a crucial role. Often those problems are too complex to be solve d analytically. Accordingly, numerical algorithms keeping track of the fluc tuations are needed. Cellular automata (CA) and Lattice Boltzmann (LB) mode ls are two possible approaches to simulate complex systems. CA models keep track of many-body correlations and provide a description of the fluctuatio ns. However, they lend to a noisy dynamics and impose a restriction on the possible values of the viscosity. On the other hand, LB models are numerica lly more efficient and offer much more flexibility to adjust the physical p arameters, but they neglect the fluctuations. We have developed a new multi particle lattice model which reconciles both approaches. The main character istics of this approach are explained, and our model is used to study the k inetics of two-dimensional ballistic annihilation. (C) 1999 Elsevier Scienc e B.V. All rights reserved.