On Locally Definitizable Matrix Functions

T. Ya. Azizov ; P. Jonas

Funkcionalʹnyj analiz i ego priloženiâ, Tome 41 (2007) no. 3, pp. 1-16.

Résumé

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 $G(\lambda)$ is a locally definitizable or locally generalized matrix Nevanlinna function, then $-(G(\lambda))^{-1}$ belongs to the same class.

Détail

Keywords: Krein space, meromorphic function, definitizable operator-function, Nevanlinna matrix-function, generalized resolvent.

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