arXiv:0712.4336 · Journal of Statistical Mechanics Theory and Experiment
Evolution of correlations of quantum many-particle systems
V. I. Gerasimenko, V. O. Shtyk
Abstract
We consider the origin of the microscopic description of correlations in quantum systems. For correlation operators that give the alternative description of the quantum state evolution of many-particle systems, we deduce the von Neumann hierarchy of nonlinear equations and discuss the relationships of its solution both with the solution of the BBGKY hierarchy and with the s -particle correlation operators. A solution of the von Neumann hierarchy is constructed in the form of an expansion over particle clusters whose evolution is described by the corresponding order cumulant (semi-invariant) of evolution operators of the von Neumann equations for the density operators. For the initial data from the space of sequences of trace class operators the existence of a strong and a weak solution of the Cauchy problem is proved.