  A modification of the covariant theory is proposed in which the self-energy
of the system, corresponding to time-like degrees of freedom in the
configuration space, preserves the classical law of change in quantum theory.
As a result, proper time in covariant quantum theory takes on a dynamic
meaning. As applications of the new formalism, a modification of the
relativistic quantum mechanics of a scalar particle and a homogeneous model of
the universe is considered.
