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arXiv · 1106.2618

$C^*$-simplicity for groups with non-elementary convergence group actions

Yoshifumi Matsuda·Shin-ichi Oguni·Saeko Yamagata
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Abstract

We prove that a countable group with an effective minimal non-elementary convergence group action is a Powers group. More strongly we prove that it is a strongly Powers group and thus its non-trivial subnormal subgroups are $C^*$-simple.

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Yoshifumi Matsuda, Shin-ichi Oguni, Saeko Yamagata. 2011-08-11. $C^*$-simplicity for groups with non-elementary convergence group actions. https://arxiv.org/abs/1106.2618

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