ArticleOriginal scientific text
Title
On a property of weak resolvents and its application to a spectral problem
Authors 1
Affiliations
- Department of Mathematics and Computer Science, Adam Mickiewicz University, Matejki 48/49, 60-769 Poznań, Poland
Abstract
We show that the poles of a resolvent coincide with the poles of its weak resolvent up to their orders, for operators on Hilbert space which have some cyclic properties. Using this, we show that a theorem similar to the Mlak theorem holds under milder conditions, if a given operator and its adjoint have cyclic vectors.
Keywords
weak resolvent, cyclic vector, spectral radius, Hardy class, operator model theory, scattering theory, control theory
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