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Factorizations and invariant subspaces for weighted Schur classes

Alexey Tikhonov
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Abstract

We study factorizations of operator valued functions of weighted Schur classes over multiply-connected domains. There is a correspondence between functions from weighted Schur classes and so-called ``conservative curved'' systems introduced in the paper. We show that the fundamental relationship between invariant subspaces of the main operator of a conservative system and factorizations of the corresponding operator valued function of Schur class, which is well known in the case of the unit disk, can be extended to our case. We develop new notions and constructions and discuss changes that should be made to the standard theory to obtain desired generalization.

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Alexey Tikhonov. 2005-10-07. Factorizations and invariant subspaces for weighted Schur classes. https://arxiv.org/abs/math/0510135

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