Realizations of Herglotz-Nevanlinna Functions via F-systems

  • Seppo Hassi
  • Henk de Snoo
  • Eduard Tsekanovskiĭ
Conference paper
Part of the Operator Theory: Advances and Applications book series (OT, volume 132)

Abstract

An extension of Brodskiĭ-CLivšic operator systems, involving an unbounded main operator and an additional orthogonal projection, is studied. It leads to new types of representation and realization results for certain classes of Herglotz-Nevanlinna functions and for the associated transfer functions.

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Copyright information

© Springer Basel AG 2002

Authors and Affiliations

  • Seppo Hassi
    • 1
  • Henk de Snoo
    • 2
  • Eduard Tsekanovskiĭ
    • 3
  1. 1.Department of Mathematics and StatisticsUniversity of Vaasa PL 700VaasaFinland
  2. 2.Department of MathematicsUniversity of GroningenGroningenNederland
  3. 3.Department of MathematicsNiagara UniversityUSA

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