Eusebio Gardella, Volodymyr Nekrashevych, Benjamin Steinberg, Alina Vdovina
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Simplicity of C*-Algebras of Contracting Self-Similar Groups
We show that the \(C^*\)-algebra associated by Nekrashevych to a contracting self-similar group is simple if and only if the corresponding complex \(*\)-algebra is simple. We also improve on Steinberg and Szakács’s algorithm to determine if the \(*\)-algebra is simple. This provides an interesting class of non-Hausdorff, amenable, effective and minimal ample groupoids for which simplicity of the \(C^*\)-algebra and the complex \(*\)-algebra are equivalent.
期刊介绍:
The mission of Communications in Mathematical Physics is to offer a high forum for works which are motivated by the vision and the challenges of modern physics and which at the same time meet the highest mathematical standards.