Jussi Behrndt (TU Berlin)

Scattering matrices and Weyl functions

Abstract:

For a scattering system consisting of two
selfadjoint extensions of a symmetric operator A
with finite deficiency indices, the scattering matrix
and a spectral shift function are expressed in terms of the
Weyl function associated with a boundary triplet for A*.
The results are applied to Sturm-Liouville operators
and Schroedinger operators with point interactions.
The talk is based on a joint paper with
Mark M. Malamud (Donetsk National University, Ukraine) and
Hagen Neidhardt (WIAS Berlin).