  The paper deals with the problem of the rigorous description of the evolution
of states of large particle quantum systems by means of correlation operators.
A nonperturbative solution of the Cauchy problem of the hierarchy of nonlinear
evolution equations for a sequence of marginal correlation operators is
constructed. For initial states specified in terms of a one-particle density
operator and correlation operators we also develop an approach to the
description of the processes of the creation and the propagation of
correlations within the framework of a one-particle density operator. Moreover,
the mean field asymptotic behavior of constructed marginal correlation
operators is established.
