Dynamic chaos: Examination of classic and quantum systems from the general standpoint Phenomenon of “selective predictability”

The reasons of formal absence of dynamic chaos in quantum theory against the classical one are analyzed by using the method of pseudo-coherent states. It is shown, that in the area, where a classic instability arises, the expansion of a wave packet in the quantum case promotes a suppression of this instability. In the cases where after widening wave packet the compression phase comes again, i.e., as if the wave packet width “pulsates”, phenomenon of a so-called “selective predictability” takes place when the dispersion of experimental results decreases a lot at certain “selective” time moments.