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A generalization of Stenger’s lemma to maximal dissipative operators. (English) Zbl 1248.47037

Let the Hilbert space \({\mathcal H}\) be the orthogonal sum \({\mathcal H=\mathcal F\oplus \mathcal G}\) of two Hilbert spaces \({\mathcal F, \mathcal G}\) with \({\text{dim}\;{\mathcal G} < \infty}\). Let \(P_{\mathcal F}\) denote the orthogonal projection in \({\mathcal H}\) onto \({\mathcal F}\).
It is shown that, for any maximal dissipative operator \(A\), the operator \(P_{\mathcal F} A|_{ \text{dom} A\cap\mathcal F}\) is again a maximal dissipative operator in \(\mathcal F\).

MSC:

47B44 Linear accretive operators, dissipative operators, etc.
47A48 Operator colligations (= nodes), vessels, linear systems, characteristic functions, realizations, etc.
Full Text: DOI

References:

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