2024/10/19 by Oleg Zubelevich, Zubelevich, Oleg
Computer Science · Mathematics · #46B25 #46C15 #47A53 #47B38 #47B48 #Advanced Topics in Algebra #Algebraic and Geometric Analysis #FOS: Mathematics #FOS: Physical sciences #Functional Analysis (math.FA) #Mathematical Physics (math-ph) #Matrix Theory and Algorithms
paper · pdf · doi:10.48550/arxiv.2411.00797
openalex publication_date 2024/10/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this short note we present a far generalization of the following very well-known assertion: assume that we have two orthonormal sequences in a Hilbert space and these sequences are quadratically close to each other. Then if one of these sequences is a basis in the Hilbert space then so is the other one.