Bull. Austral. Math. Soc. 72(2) pp.197--212, 2005.

On C*-algebras with the approximate n-th root property

A. Chigogidze

A. Karasev

K. Kawamura

V. Valov

Received: 3rd March, 2005

The second author was partially supported by his NSERC Grant 257231-04.
The paper was started during the third author's visit to Nipissing University in July 2004.
The last author was partially supported by his NSERC Grant 261914-03.

Abstract

We say that a C*-algebra X has the approximate n-th root property (n $ \geq $ 2) if for every a $ \in $ X with |a| $ \leq $ 1 and every $ \varepsilon $ > 0 there exists b $ \in $ X such that |b| $ \leq $ 1 and |a - bn| < $ \varepsilon $. Some properties of commutative and non-commutative C*-algebras having the approximate n-th root property are investigated. In particular, it is shown that there exists a non-commutative (respectively, commutative) separable unital
C*-algebra X such that any other (commutative) separable unital C*-algebra is a quotient of X. Also we illustrate a commutative C*-algebra, each element of which has a square root such that its maximal ideal space has infinitely generated first Čech cohomology.

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(Metadata: XML, RSS, BibTeX) MathSciNet: MR2183403 Z'blatt-MATH: 02246384

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