Approximation by invertible and noninvertible operators
type: Item
instance of: scholarly article
title: Approximation by invertible and noninvertible operators
zbMATH Open document ID: 0673.41017
DOI: 10.1016/0021-9045(89)90116-0
published in: Journal of Approximation Theory
publication date: 1989-01-01T00:00:00Z
review text: Let T be a bounded linear operator on a complex separable Hilbert space. The author considers the approximation of T by operators with unequal kernel dimension and determines \(\inf \{\| T-S\|:\) dim ker \(S\neq \dim \ker T\}\). This problem is related to that of approximating T by invertible operators and by noninvertible operators.
Mathematics Subject Classification ID: 41A36
Mathematics Subject Classification ID: 41A65
Mathematics Subject Classification ID: 47A99
zbMATH DE Number: 4101795
zbMATH Keywords: invertible operators
author: Pei Yuan Wu
reviewed by: Ioan Raşa
MaRDI profile type: Publication
full work available at URL: 0021-9045(89)90116-0
OpenAlex ID: W2088887266
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description: scientific article; zbMATH DE number 4101795