  The systematic theory of the formation of the short light pulses in the
squeezed state during the propagation in a medium with inertial Kerr
nonlinearity is developed. The algebra of time-dependent Bose-operators is
elaborated and the normal-ordering theorem for them is formulated. It is
established that the spectral region where the quadrature fluctuations are
weaker than the shot-noise, depends on both the relaxation time of the
nonlinearity and the magnitude of the nonlinear phase shift. It is also shown
that the frequency at which suppression of the fluctuation is greatest can be
controlled by adjusting the phase of the initial coherent light pulse. The
spectral correlation function of photons is introduced and photon antibunching
is found.
