Inclusion of Diffraction Effects in the Gutzwiller Trace Formula
  The Gutzwiller trace formula is extended to include diffraction effects. The new trace formula involves periodic rays which have non-geometrical segments as a result of diffraction on the surfaces and edges of the scatter. 
G. Vattay (Institute for Solid State Physics, E\"otv\"os University,   M\'uzeum krt. 6-8, H-1088 Budapest, Hungary), A. Wirz...