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On the regularity of the critical point infinity of definitizable operators

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Abstract

In this note necessary and sufficient conditions for the regularity of the critical point infinity of a definitizable operator A are given. Using these criteria it is proved that the regularity of the critical point infinity is preserved under some additive perturbations as well as for some operators which are related to A. Applications to indefinite Sturm-Liouville problems are indicated.

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  1. Prirodno-matematički fakultet, Univerziteta u Sarajevu, Vojvode Putnika 43, YU 71000, Sarajevo, Yugoslavia

    Branko Ćurgus

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Ćurgus, B. On the regularity of the critical point infinity of definitizable operators. Integr equ oper theory 8, 462–488 (1985). https://doi.org/10.1007/BF01204699

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