Master equation and molecular dynamics simulations of spatiotemporal effects in a bistable chemical system

A simple and realistic model of a bistable chemical system in which running fronts can be observed is studied. The stochastic dynamics of this model i s described by the master equation for a spatially extended system. The res ults are compared with microscopic simulations of the system, performed usi ng the molecular dynamics technique for reactive hard spheres. The velocity of the front and its shape obtained in both simulations agree well with th e phenonenological description. For small volumes of the systems fluctuatio ns grow locally and create pulses of concentrations.