Multipoint selfadjoint quasi-differential operators for first order

Abstract

In the present paper, the aim is to described all selfadjoint extensions of the minimal operator generated by first order linear symmetric multipoint quasi-differential operator expression in the direct sum of weighted Hilbert spaces of vector-functions defined at the semi-infinite intervals by using the Calkin-Gorbachuk method. We have also examine the structure of the spectrum of such extensions.

Keywords

• Symmetric and selfadjoint differential operators,multipoint quasi-differential expression,deficiency indices,spectrum

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