Systems of two subspases in a Hilbert space

2018/10/12 by Masatoshi Enomoto, Enomoto, Masatoshi, Yasuo Watatani +1
Mathematics · #46C07 #47A15 #Advanced Operator Algebra Research #Advanced Topics in Algebra #FOS: Mathematics #Functional Analysis (math.FA) #Spectral Theory in Mathematical Physics #math.FA #msc:46C07 #msc:47A15

paper · pdf · doi:10.48550/arxiv.1810.05397

13 pages

arxiv created 2018/10/12 · openalex publication_date 2018/10/12 · arxiv updated 2018/10/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We study two subspace systems in a separable infinite-dimensional Hilbert space up to (bounded) isomorphism. One of the main result of this paper is the following: Isomorphism classes of two subspace systems given by graphs of bounded operators are determined by unitarily equivalent classes of the operator ranges and the nullity of the original bounded operators giving graphs. We construct several non-isomorphic examples of two subspace systems in an infinite-dimensional Hilbert space.

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