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arXiv · 1409.1395

When central sequence C*-algebras have characters

Eberhard Kirchberg·Mikael Rordam
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Abstract

We investigate C*-algebras whose central sequence algebra has no characters, and we raise the question if such C*-algebras necessarily must absorb the Jiang-Su algebra (provided that they also are separable). We relate this question to a question of Dadarlat and Toms if the Jiang-Su algebra always embeds into the infinite tensor power of any unital C*-algebra without characters. We show that absence of characters of the central sequence algebra implies that the C*-algebra has the so-called strong Corona Factorization Property, and we use this result to exhibit simple nuclear separable unital C*-algebras whose central sequence algebra does admit a character. We show how stronger divisibility properties on the central sequence algebra imply stronger regularity properties of the underlying C*-algebra.

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Eberhard Kirchberg, Mikael Rordam. 2014-09-04. When central sequence C*-algebras have characters. https://arxiv.org/abs/1409.1395

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