The characteristic function of a complex symmetric contraction

Chevrot, Nicolas; Fricain, Emmanuel; Timotin, Dan

doi:10.1090/S0002-9939-07-08803-X

The characteristic function of a complex symmetric contraction
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by Nicolas Chevrot, Emmanuel Fricain and Dan Timotin PDF

Proc. Amer. Math. Soc. 135 (2007), 2877-2886 Request permission

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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