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A perturbation method and the limit-point case of even order symmetric differential expressions

Published online by Cambridge University Press:  14 November 2011

Bernhard Mergler  and
Bernd Schultze
Bernhard Mergler
Affiliation:
Fachbereich 6-Mathematik, Universität Essen-Gesamthochschule, Universitätsstrasse 3, D-4300 Essen 1, West Germany
Bernd Schultze
Affiliation:
Fachbereich 6-Mathematik, Universität Essen-Gesamthochschule, Universitätsstrasse 3, D-4300 Essen 1, West Germany
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Synopsis

We give a new perturbation theorem for symmetric differential expressions (relatively bounded perturbations, with relative bound 1) and prove with this theorem a new limit-point criterion generalizing earlier results of Schultze. We also obtain some new results in the fourth-order case.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 94 , Issue 1-2 , 1983 , pp. 121 - 135
Copyright
Copyright © Royal Society of Edinburgh 1983

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