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Singular non-selfadjoint differential operators

Published online by Cambridge University Press:  14 November 2011

Sobhy El-sayed Ibrahim
Sobhy El-sayed Ibrahim
Affiliation:
Benha University, Faculty of Science, Department of Mathematics, BenhaB 13518, Egypt
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Abstract

A characterisation is obtained of all the regularly solvable operators and their adjoints generated by general ordinary quasidifferential expressions in The domains of these operators are described in terms of boundary conditions involving the solutions of M[u] = λwu and the adjoint equation at both singular end-points a and b. These results are an extension of those proved in [3], by Evans and Ibrahim, to the case of two singular end-points of the interval (a, b), and a generalisation of those in [10] and [13] concerning selfadjoint and J-selfadjoint differential operators, where J denotes complex conjugation.

Type
Research Article
Information
Proceedings of the Royal Society of Edinburgh Section A: Mathematics , Volume 124 , Issue 4 , 1994 , pp. 825 - 841
Copyright
Copyright © Royal Society of Edinburgh 1994

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