Abstract
For a closed symmetric operator or relation, Kre 137-1 n’s formula describes all its self-adjoint extensions in terms of certain holomorphic parameters. Our interest is in self-adjoint extensions of a symmetric relation which extends itself an orthogonal sum of two symmetric relations. The corresponding class of parameters in Kre 137-2 n’s formula is idcntificd. This leads to a description of (minimal) self-adjoint extensions in a fixed exit space.
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Hassi, S., Kaltenbäck, M., de Snoo, H.S.V. (1998). The sum of matrix nevanlinna functions and self-adjoint extensions in exit spaces. In: Gohberg, I., Mennicken, R., Tretter, C. (eds) Recent Progress in Operator Theory. Operator Theory Advances and Applications, vol 103. Birkhäuser, Basel. https://doi.org/10.1007/978-3-0348-8793-9_8
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DOI: https://doi.org/10.1007/978-3-0348-8793-9_8
Publisher Name: Birkhäuser, Basel
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