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arXiv · 2308.05488

Wiener-Hopf indices of unimodular functions on the unit circle, revisited

A. E. Frazho·M. A. Kaashoek·A. C. M. Ran·F. van Schagen
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Abstract

Inspired by the paper of Groenewald, Kaashoek and Ran (Wiener-Hopf indices of unitary functions on the unit circle in terms of realizations and related results on Toeplitz operators. \emph{Indag. Math.} 28, (2017), 649-710), we present an operator-theoretic approach to provide further insight and simpler computational formulas for the Wiener-Hopf indices of a rational matrix valued function taking unimodular values on the unit circle.

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A. E. Frazho, M. A. Kaashoek, A. C. M. Ran, F. van Schagen. 2023-08-10. Wiener-Hopf indices of unimodular functions on the unit circle, revisited. https://arxiv.org/abs/2308.05488

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