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THE SIMILARITY DEGREE OF SOME ${C}^{\ast } $-ALGEBRAS

Part of: Topological algebras, normed rings and algebras, Banach algebras Selfadjoint operator algebras Topological linear spaces and related structures Methods of category theory in functional analysis General theory of linear operators

Published online by Cambridge University Press:  27 June 2013

DON HADWIN  and
WEIHUA LI
DON HADWIN*
Affiliation:
Department of Mathematics, University of New Hampshire, Durham, NH 03824, USA
WEIHUA LI
Affiliation:
Science and Mathematics Department, Columbia College Chicago, Chicago, IL 60605, USA email [email protected]
*
✉[email protected]
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Abstract

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We define the class of weakly approximately divisible unital ${C}^{\ast } $-algebras and show that this class is closed under direct sums, direct limits, any tensor product with any ${C}^{\ast } $-algebra, and quotients. A nuclear ${C}^{\ast } $-algebra is weakly approximately divisible if and only if it has no finite-dimensional representations. We also show that Pisier’s similarity degree of a weakly approximately divisible ${C}^{\ast } $-algebra is at most five.

Keywords

Kadison similarity problemsimilarity degreetracially nuclearC∗-algebra

MSC classification

Secondary: 46L05: General theory of $C^*$-algebras 46A22: Theorems of Hahn-Banach type; extension and lifting of functionals and operators 46H25: Normed modules and Banach modules, topological modules (if not placed in or ) 46M10: Projective and injective objects 47A20: Dilations, extensions, compressions
Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 89 , Issue 1 , February 2014 , pp. 60 - 69
Copyright
Copyright ©2013 Australian Mathematical Publishing Association Inc. 

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