ON THE DECAY OF MANY-BODY SYSTEM

The existence of particle outflow in the decay of many-body system lea ds to a special description with two sets of state eigenvectors and co rresponding complex eigenvalues. Using such eigenvectors the general t ime behavior of the decaying system is obtained. As an example, we con sider the problem of a particle decay of the many-body system to demon strate the difference between this problem and the problem of a single particle in potential well. We also consider the case of particle sca ttering by an optical potential and show that the existence of outflow also leads to two sets of state eigenvectors, but with real energy ei genvalues.