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arXiv · 2610.36459

Classification of reduced free products of nuclear C*-algebras

George A. Elliott·Chun Guang Li·Zhuang Niu
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Abstract

Consider the countably infinite reduced free product $D$ of copies of $(\mathrm C([0,1]),λ)$, where $λ$ is Lebesgue measure. It is proved that finite and countable reduced free products of unital separable nuclear UCT $\mathrm C^*$-algebras with respect to a chosen family of faithful traces are classified, after adjoining $D$, by the Elliott invariant. In other words, an isomorphism between the naive K-theory invariants of two such algebras is induced by an isomorphism between the algebras.

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George A. Elliott, Chun Guang Li, Zhuang Niu. 2026-10-27. Classification of reduced free products of nuclear C*-algebras. https://arxiv.org/abs/2610.36459

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