Abstract:
A study is made of a nonrelativistic model problem of the stability of phase functions in the
case of scattering of a particle by a random time-independent potential. It is shown that
the phase functions may be either stable or unstable depending on the parameters of the
problem; a criterion is given for the changeover from stable to unstable conditions. In the
latter case, the Usual quantum-mechanical treatment is incorrect and one must introduce
an additional averaging procedure. This is a necessary sign of the statistical nature of
the system. The instability criterion obtained is used in a discussion of the properties of
intermediate compound systems that arise in the interaction of hadrons with nuclei and with
one another.