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

2023/08/10 by Frazho, A. E., Kaashoek, M. A., Ran, A. C. M. +1
#47A53 #47A56 #47A68 #47B35 #FOS: Mathematics #Functional Analysis (math.FA)

paper · doi:10.48550/arxiv.2308.05488

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. 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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