Spectral Theory in Inner Product Spaces and Applications: 6th Workshop on Operator Theory in Krein Spaces and Operator Polynomials, Berlin, December 2006

Description

This book contains a collection of recent research papers originating from the 6th Workshop on Operator Theory in Krein Spaces and Operator Polynomials, which was held at the TU Berlin, Germany, December 14 to 17, 2006. The contributions in this volume are devoted to spectral and perturbation theory of linear operators in spaces with an inner product, generalized Nevanlinna functions and problems and applications in the field of differential equations. Among the discussed topics are linear relations, singular perturbations, de Branges spaces, nonnegative matrices and abstract kinetic equations. Front Matter....Pages i-xx Augmented Schur Parameters for Generalized Nevanlinna Functions and Approximation....Pages 1-30 On Domains of Powers of Linear Operators and Finite Rank Perturbations....Pages 31-36 Finite-dimensional de Branges Subspaces Generated by Majorants....Pages 37-48 Trace Formulae for Dissipative and Coupled Scattering Systems....Pages 49-85 Approximation of N κ ∞ -functions I: Models and Regularization....Pages 87-112 On the Block Numerical Range of Nonnegative Matrices....Pages 113-133 A Quantum Dot with Impurity in the Lobachevsky Plane....Pages 135-148 One-dimensional Perturbations, Asymptotic Expansions, and Spectral Gaps....Pages 149-173 Abstract Kinetic Equations with Positive Collision Operators....Pages 175-195 On the Structure of Semigroups of Operators Acting in Spaces with Indefinite Metric....Pages 197-205 G -Self-adjoint Operators in Almost Pontryagin Spaces....Pages 207-235 On a Kreĭn Criterion....Pages 237-243 Two-sided Weighted Shifts Are ‘Almost Krein’ Normal....Pages 245-250