Abstract
Realization theory is used to study Nevanlinna-Pick and Carathéodory-Fejér interpolation problems for generalized Schur classes. In the first part of the paper, conditions are given for the existence of a solution of a factorization problem that includes Nevanlinna-Pick interpolation and factorization problems of Leech type for operator-valued functions. In the second part, an analysis is made of the numbers of positive and negative eigenvalues of classical matrices which arise in coefficient problems. The complete solution of an indefinite Carathéodory-Fejér problem is obtained.
Keywords
- Hilbert Space
- Negative Eigenvalue
- Interpolation Problem
- Selfadjoint Operator
- Partial Isometry
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
To Harry Dym: teacher, colleague and friend, in appreciation and with best wishes.
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Alpay, D., Constantinescu, T., Dijksma, A., Rovnyak, J. (2002). Notes on Interpolation in the Generalized Schur Class. I. Applications of Realization Theory. In: Alpay, D., Vinnikov, V., Gohberg, I. (eds) Interpolation Theory, Systems Theory and Related Topics. Operator Theory: Advances and Applications, vol 134. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-8215-6_5
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DOI: https://doi.org/10.1007/978-3-0348-8215-6_5
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