Functional Analysis and Its Applications

, Volume 41, Issue 3, pp 169–180 | Cite as

On locally definitizable matrix functions

  • T. Ya. Azizov
  • P. Jonas


We study analytic properties of special classes of matrix functions (locally definitizable and locally Nevanlinna functions) by methods of operator theory. The aim of this paper is to prove that if G(λ) is a locally definitizable or locally generalized matrix Nevanlinna function, then −(G(λ))−1 belongs to the same class.

Key words

Krein space meromorphic function definitizable operator-function Nevanlinna matrix-function generalized resolvent 


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • T. Ya. Azizov
    • 1
  • P. Jonas
    • 2
  1. 1.Voronezh State UniversityVoronezh
  2. 2.Technical University of BerlinBerlin

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