Selfadjoint extensions of a singular multipoint differential operator of first order

In this work, we describe all selfadjoint extensions of the minimal operator generated by linear singular multipoint symmetric differential expression $l=(l_1,l_2,l_3)$, $l_k=ifrac{d}{dt}+A_k$ with selfadjoint operator coefficients $A_k$, $k=1,2,3$ in a Hilbert space. This is done as a direct su...

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Bibliographic Details
Main Authors: Zameddin I. Ismailov, Rukiye Ozturk Mert
Format: Article
Language:English
Published: Texas State University 2013-05-01
Series:Electronic Journal of Differential Equations
Subjects:
Online Access:http://ejde.math.txstate.edu/Volumes/2013/129/abstr.html
Description
Summary:In this work, we describe all selfadjoint extensions of the minimal operator generated by linear singular multipoint symmetric differential expression $l=(l_1,l_2,l_3)$, $l_k=ifrac{d}{dt}+A_k$ with selfadjoint operator coefficients $A_k$, $k=1,2,3$ in a Hilbert space. This is done as a direct sum of Hilbert spaces of vector-functions $$ L_2(H,(-infty ,a_1))oplus L_2(H,(a_2,b_2)) oplus L_2(H,(a_3,+infty)) $$ where $-infty <a_1<a_2<b_2<a_3<+infty$. Also, we study the structure of the spectrum of these extensions.
ISSN:1072-6691