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arXiv · 1006.2275

Multi-operator colligations and multivariate characteristic functions

Yury A. Neretin
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Abstract

In the spectral theory of non-self-adjoint operators there is a well-known operation of product of operator colligations. Many similar operations appear in the theory of infinite-dimensional groups as multiplications of double cosets. We construct characteristic functions for such double cosets and get semigroups of matrix-valued functions in matrix balls.

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Yury A. Neretin. 2010-06-11. Multi-operator colligations and multivariate characteristic functions. https://doi.org/10.1007/s13324-011-0009-y

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