The invariant subspaces of S⊕ S^*

2020/03/20 by Dan Timotin, Timotin, Dan
Mathematics · #47A15 #47A45 #47B37 #Advanced Operator Algebra Research #FOS: Mathematics #Functional Analysis (math.FA) #Holomorphic and Operator Theory #Spectral Theory in Mathematical Physics

paper · pdf · doi:10.48550/arxiv.2003.09399

openalex publication_date 2020/03/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Using the tools of Sz.-Nagy--Foias theory of contractions, we describe in detail the invariant subspaces of the operator S⊕ S^* , where S is the unilateral shift on a Hilbert space. This answers a question of Câmara and Ross.

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