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On Positivity and Roots in Operator Algebras

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Abstract

In earlier papers the second author and Charles Read have introduced and studied a new notion of positivity for operator algebras, with an eye to extending certain C*-algebraic results and theories to more general algebras. The present paper consists of complements to some facts in the just mentioned papers, concerning this notion of positivity. For example we prove a result on the numerical range of products of the roots of commuting operators with numerical range in a sector.

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Correspondence to David P. Blecher.

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C. A. Bearden and D. P. Blecher were supported by a grant from the NSF.

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Bearden, C.A., Blecher, D.P. & Sharma, S. On Positivity and Roots in Operator Algebras. Integr. Equ. Oper. Theory 79, 555–566 (2014). https://doi.org/10.1007/s00020-014-2136-y

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  • DOI: https://doi.org/10.1007/s00020-014-2136-y

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