Positive elements and the \(B^ *\) condition
type: Item
instance of: scholarly article
title: Positive elements and the \(B^ *\) condition
zbMATH Open document ID: 0611.46061
DOI: 10.1007/BF01163350
author: B. George
published in: Mathematische Zeitschrift
publication date: 1986-01-01T00:00:00Z
full work available at URL: https://eudml.org/doc/173764
review text: The basic theory of the ''positive elements'' of a \(B^*\)-algebra is derived from the \(B^*\) condition by a combination of totally elementary argument, the spectral radius formula and the square root lemma. In the process a sort of ''topological norm additivity'' emerges for positive elements. In this note we do two things: we try to properly locate the additivity condition in the development of the theory of positive elements, and we use it to extend ''spectral permanence'' from single elements to more general systems.
Mathematics Subject Classification ID: 46L05
zbMATH DE Number: 3988007
zbMATH Keywords: positive elements of a \(B^ *\)-algebra
zbMATH Keywords: spectral radius formula
zbMATH Keywords: square root lemma
zbMATH Keywords: topological norm additivity
zbMATH Keywords: spectral permanence
MaRDI profile type: Publication
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description: scientific article; zbMATH DE number 3988007