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% Revision 1.2  1997/12/18 08:34:31  bert
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% Revision 1.1  93/05/14  14:56:25  starflt
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% Revision 1.1  90/05/04  10:41:01  lwvanels
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%% The text of your abstract and nothing else (other than comments) goes here.
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Quantum-mechanical return probabilities are suggested as a way to
analyze the recurrent behavior of quantum-mechanical dynamical
systems.  An analogy is drawn between the maxima of return
probabilities for a system and the periodic orbits of the analogous
classical system.

A numerical model for modeling the time evolution of a
quantum-mechanical state, by iterated application of short-term
time-evolution operators to a discretely sampled wave function, is
introduced and evaluated.  The requirements of such a computational
model are analyzed.

This computational model is then applied to the study of return
probabilities for a small problem targeted to run on workstation-class
computers.  Return probabilities are calculated for Gaussian wave
packets whose coordinates and momenta correspond to the classical
energy $E=0.3$.  The resulting data demonstrates a high degree of
correspondence between the maxima of return probabilities and the
corresponding classical periodic orbits, but also demonstrates some of
the ways in which discrepancies may arise.
