Abstract
In this paper we give an analogue of Krein's formula on the description of generalized resolvents of a symmetryS in the case that theS acts in a degenerated inner product space. These results are applied to the extension problem of positive definite functions.
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The first author was supported by “Fonds zur Förderung der wissenschaftlichen Forschung” of Austria, Project P 09832-MAT.
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Kaltenbäck, M., Woracek, H. Selfadjoint extensions of symmetric operators in degenerated inner product spaces. Integr equ oper theory 28, 289–320 (1997). https://doi.org/10.1007/BF01294155
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DOI: https://doi.org/10.1007/BF01294155