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Every Invertible Hilbert Space Operator is a Product of Seven Positive Operators

Published online by Cambridge University Press:  20 November 2018

N. Christopher Phillips
N. Christopher Phillips*
Affiliation:
Department of Mathematics, University of Oregon, Eugene, Oregon 97403-1222, U.S.A.
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Abstract

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We prove that every invertible operator in a properly infinite von Neumann algebra, in particular in L(H) for infinite dimensional H, is a product of 7 positive invertible operators. This improves a result of Wu, who proved that every invertible operator in L(H) is a product of 17 positive invertible operators.

Keywords

47B99
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 38 , Issue 2 , 01 June 1995 , pp. 230 - 236
Copyright
Copyright © Canadian Mathematical Society 1995

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