This is a volume dedicated to Heinz Langer. It includes biographical material and carefully selected papers.
Heinz Langer has made fundamental contributions to operator theory. In particular, he studied the domains of operator pencils and nonlinear eigenvalue problems, the theory of indefinite inner product spaces, operator theory in Pontryagin and Krein spaces, and applications to mathematical physics. His works include studies on and applications of Schur analysis in the indefinite setting, where the factorization theorems of Krein and Langer for generalized Schur functions and of Dijksma-Langer-Luger-Shondin play a key role.
The contributions in this volume reflect Heinz Langer's research interests and will be appealing to a broad research audience in operator theory.