  The finite duration of collisions appear as time-nonlocality in the kinetic
equation. Analyzing the corresponding quantum kinetic equation for dense
interacting Fermi systems a delay differential equation is obtained which
combines time derivatives with finite time stepping known from the logistic
mapping. The responsible delay time is explicitly calculated and discussed. As
a novel feature oscillations in the time evolution of the distribution function
itself appear and bifurcations up to chaotic behavior can occur. The
temperature and density conditions are presented where such oscillations and
bifurcations arise indicating an onset of phase transition.
