Abstract
The paper deals with the boundary indefinite interpolation problem in the classes of generalized Nevanlinna matrix functions. A one-to-one correspondence between the set of all solutions of the problem and the class of so-called \(G\)-regular self-adjoint extensions of the model symmetric operator associated with the problem is established. Sufficient conditions for the \(G\)-regularity of self-adjoint extensions (in terms of the Weyl function) are given. A formula for the description of all the solutions of the problem is obtained.
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Amirshadyan, A.A. Boundary Interpolation Problem in the Classes of Generalized Nevanlinna Matrix Functions. Mathematical Notes 73, 163–167 (2003). https://doi.org/10.1023/A:1022198723098
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DOI: https://doi.org/10.1023/A:1022198723098