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arXiv · 1309.6882

Q-functions and boundary triplets of nonnegative operators

Yury Arlinskii·Seppo Hassi
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Abstract

Operator-valued $Q$-functions for special pairs of nonnegative selfadjoint extensions of nonnegative not necessarily densely defined operators are defined and their analytical properties are studied. It is shown that the Kre\uın-Ovcharenko statement announced in \cite{KrO2} is valid only for $Q$-functions of densely defined symmetric operators with finite deficiency indices. A general class of boundary triplets for a densely defined nonnegative operator is constructed such that the corresponding Weyl functions are of Kre\uın-Ovcharenko type.

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Yury Arlinskii, Seppo Hassi. 2013-09-26. Q-functions and boundary triplets of nonnegative operators. https://arxiv.org/abs/1309.6882

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