This paper is a further development of the approach in quantum statistical mechanics proposed by the author. The hierarchy of equations for reduced density matrices obtained previously is extended to the case corresponding to the Bose condensation. The relevant state of the system with a...

In previous publications by the author the crystalline state was studied with the help of statistical methods based upon utilization of distribution functions. The approximation used for a crystal was not, however, fully adequate for fluids, which did not permit one, in particular, to construct...

The approach in equilibrium statistical mechanics proposed by the author in a previous publication is extended to studies of the crystalline state. In the classical case considered in this paper, the approach leads to the equilibrium BBGKY hierarchy. The distinctive feature of the approach in...

The quantum hierarchy of equations for equilibrium density matrices obtained earlier by the author is extended to studies of the crystalline state. The thermodynamics of a crystal is constructed consistently with periodic solutions of the hierarchy. The structure of the pair correlation function...