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On Representations of Matrix Valued Nevanlinna Functions by u - Resolvents

✍ Scribed by Michael Kaltenbäck; Harald Woracek


Publisher
John Wiley and Sons
Year
2010
Tongue
English
Weight
662 KB
Volume
205
Category
Article
ISSN
0025-584X

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✦ Synopsis


We show that every matrix valued generalized Nevanlinna function can be represented w a u-resolvent of a certain selfadjoint relation acting in a Pontryagin space. The negative index of this Pontryagin space may be larger than the number of negative squares of the given function.

The minimal index of negative squares which is needed to obtain such a representation is determined.

In the case of scalar functions, the results presented give rise to some new classes of generalized Nevanlinna functions.


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