On quasi-continuous approximation in classical statistical mechanics

Abstract

A continuous infinite system of point particles with strong superstable interaction is considered in the framework of classical statistical mechanics. The family of approximated correlation functions is determined in such a way, that they take into account only such configurations of particles in $\mathbb{R}^d$ which for a given partition of the configuration space $\mathbb{R}^d$ into nonintersecting hyper cubes with a volume $a^d$ contain no more than one particle in every cube. We prove that these functions converge to the proper correlation functions of the initial system if the parameter of approximation $a\rightarrow 0$ for any positive values of an inverse temperature $\beta$ and a fugacity $z$. This result is proven both for two-body interaction potentials and for many-body case.