Stochastic positive P-representation in problems of quantum statistics. Simulation of one-dimensional Bose-gas with delta-repulsion

A method of stochastic positive P-representation for the computer simulation of thermal equilibrium and dynamical properties of many-particle quantum systems with interactions is proposed and thoroughly analyzed. The testing procedure of the method includes the evaluation of spatial correlation functions for the one-dimensional Bose-gas with delta-repulsion between particles, both in the state of thermal equilibrium and in the dynamical evolution from a given initial state. This work was supported by the Russian Foundation for Basic Research (project number 08-02-00041) and by the Royal Swedish Academy of Sciences.