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An infinite family of non-isomorphic C*-algebras with identical K-theory

Andrew S. Toms
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Abstract

We exhibit a countably infinite family of simple, separable, nuclear, and mutually non-isomorphic C*-algebras which agree on K-theory and traces. The algebras do not absorb the Jiang-Su algebra Z tensorially, answering a question of N. C. Phillips. They are also pairwise shape and Morita equivalent. The distinguishing invariant is the radius of comparison, a non-stable invariant of the Cuntz semigroup.

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Andrew S. Toms. 2007-08-22. An infinite family of non-isomorphic C*-algebras with identical K-theory. https://arxiv.org/abs/math/0609214

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