Geometry of spectral bounds of curves of unitary operators

2023/10/10 by Martín Miglioli, Miglioli, Martin
Engineering · Mathematics · #22E65 #47A10 #58B20 #58E50 #Advanced Numerical Analysis Techniques #FOS: Mathematics #Functional Analysis (math.FA) #Holomorphic and Operator Theory #Mathematical Analysis and Transform Methods

paper · pdf · doi:10.48550/arxiv.2310.06331

openalex publication_date 2023/10/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01

Abstract

This article presents a new proof of a theorem concerning bounds of the spectrum of the product of unitary operators and a generalization for differentiable curves of this theorem. The proofs involve metric geometric arguments in the group of unitary operators and the sphere where these operators act.

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