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The characteristic function of a complex symmetric contraction

Nicolas Chevrot·Emmanuel Fricain·Dan Timotin
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Abstract

It is shown that a contraction on a Hilbert space is complex symmetric if and only if the values of its characteristic function are all symmetric with respect to a fixed conjugation. Applications are given to the description of complex symmetric contractions with defect indices equal to 2.

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Nicolas Chevrot, Emmanuel Fricain, Dan Timotin. 2006-04-09. The characteristic function of a complex symmetric contraction. https://arxiv.org/abs/math/0604199

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