A reproducing kernel space model for 𝐍_{𝜅}-functions

Derkach, Vladimir; Hassi, Seppo

doi:10.1090/S0002-9939-03-06946-6

A reproducing kernel space model for $\mathbf {N}_\kappa$-functions
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by Vladimir Derkach and Seppo Hassi

Proc. Amer. Math. Soc. 131 (2003), 3795-3806

DOI: https://doi.org/10.1090/S0002-9939-03-06946-6

Published electronically: March 25, 2003

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Abstract:

A new model for generalized Nevanlinna functions $Q\in \mathbf {N}_\kappa$ will be presented. It involves Bezoutians and companion operators associated with certain polynomials determined by the generalized zeros and poles of $Q$. The model is obtained by coupling two operator models and expressed by means of abstract boundary mappings and the corresponding Weyl functions.

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