04/04/2003, 14:00 — 16:00 — Room P3.10, Mathematics Building
Frank-Olme Speck, Instituto Superior Técnico, U.T. Lisboa
On a Class of Wedge Diffraction Problems Posted by Erhard Meister
A class of canonical wedge diffraction problems was formulated
by E. Meister in 1986 and subsequently treated by an operator
theoretical approach in various publications of his research group.
Certain subclasses of those problems, recognized of being unsolved,
are subject of the present talk. Some of them are now successfully
attacked by the help of
- operator relations,
- a new factorization approach for convolution type operators
with symmetry, and
- the method of minimal normalization in Sobolev spaces.
Several gaps of the existing theory are filled, new problems are
recognized reflecting the challenges of the present state of the
art. The talk is mainly based upon joint recent work with L. Castro
and F. S. Teixeira.