**
Below is the ascii version of the abstract for 97-464.
The html version should be ready soon.**Benatti, F., Hudetz, T., Knauf, A.
Quantum Chaos and Dynamical Entropy
(1457K, Postscript)
ABSTRACT. We review the notion of dynamical entropy by Connes, Narnhofer
and Thirring and relate it to Quantum Chaos. A particle in a periodic
potential is used as an example. This is worked out
in the classical and the quantum mechanical framework, for the single
particle as well as for the corresponding gas.
The comparison does not only support the general assertion that quantum
mechanics is qualitatively less chaotic than classical mechanics.
More specifically, the same dynamical mechanism by which
a periodic potential leads to a positive dynamical entropy of the classical
particle may reduce the dynamical entropy of the quantum gas
in comparison to free motion.