  The mechanism of irreversible dynamics in the mixing systems is constructed
in the frames of the classical mechanics laws. The offered mechanism can be
found only within the framework of the generalized Hamilton's formalism. The
generalized formalism is created by expansion of the canonical Hamilton's
formalism to the open systems. A formula, which expresses the entropy through
the work of subsystems interaction forces was obtained. The essential link
between thermodynamics and classical mechanics was established.
