The papers contained in this volume are lectures and seminars presented
at the 20th "Universitatswochen fUr Kernphysik" in Schladming in
February 1981. The goal of this school was to review some rapidly
developing branches in mathematical physics. Thanks to the generous
support provided by the Austrian Federal Ministry of Science and
Research, the Styrian Government and other sponsors, it has been
possible to keep up with the - by now already traditional - standards of
this school. The lecture notes have been reexamined by the authors after
the school and are now published in their final form, so that a larger
number of physicists may profit from them. Because of necessary
limitations in space all de- tails connected with the meeting have been
omitted and only brief outlines of the seminars were incl ded. It is a
pleasure to thank all the lecturers for their efforts, which made it
possible to speed up the publi- cation. Thanks are also due to Mrs.
Krenn for the careful typing of the notes. H. Mitter L. Pittner Acta
Physica Austriaca, Supp\ XXIII, 3-28 (1981) (c) by Springer-Verlag 1981
CLASSICAL SCATTERING THEORY+ by W. THIRRING Institut fur Theoretische
Physik Universitat Wien, Austria 1. INTRODUCTION It was first recognized
by Hunziker [1] that the notions of scattering theory play an
important role in classical mechanics. It turned out [2] that it leads
to non-trivial information for the global properties of the solutions of
the classical trajectories.