Normal differential operators of first-order with smooth coefficients. (English) Zbl 1244.47011
The authors study normal extensions of a class of formally normal minimal operators, generated by a linear differential operator expression of first order in a Hilbert space of vector functions in a finite interval. The structure of the spectrum of the normal extensions is investigated.
Reviewer: Alexey Fedoseev (Saratov)
MSC:
| 47A20 | Dilations, extensions, compressions of linear operators |
| 47A10 | Spectrum, resolvent |
| 47E05 | General theory of ordinary differential operators |
| 34G10 | Linear differential equations in abstract spaces |
Keywords:
differential operator; formally normal operator; normal operator; minimal and maximal operators; extension; spectrum of an operatorReferences:
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