Mapping class groups and outer automorphism groups of free groups are C*-simple

Martin R. Bridson; Pierre de la Harpe

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Mapping class groups and outer automorphism groups of free groups are C*-simple

Martin R. Bridson·Pierre de la Harpe

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Abstract

We prove that the reduced C*-algebras of centerless mapping class groups and outer automorphism groups of free groups are simple, as are the irreducible pure subgroups of mapping class groups and the analogous subgroups of outer automorphism groups of free groups.

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Martin R. Bridson, Pierre de la Harpe. 2003-06-12. Mapping class groups and outer automorphism groups of free groups are C*-simple. https://arxiv.org/abs/math/0306204

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