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

Published online by Cambridge University Press:  27 June 2013

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]
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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.

Type
Research Article
Copyright
Copyright ©2013 Australian Mathematical Publishing Association Inc. 

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