Symmetric Functional Model for Extensions of Hermitian Operators.dvi
نویسنده
چکیده
This paper offers the functional model of a class of non-selfadjoint extensions of a Hermitian operator with equal deficiency indices. The explicit form of dilation of a dissipative extension is offered and the symmetric form of Sz.Nagy-Foiaş model as developed by B. Pavlov is constructed. A variant of functional model for a general non-selfadjoint non-dissipative extension is formulated. We illustrate the theory by two examples: singular perturbations of the Laplace operator in L2(R ) by a finite number of point interactions, and the Schrödinger operator on the half axis (0,∞) in the Weyl limit circle case at infinity.
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تاریخ انتشار 2006