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arXiv · 2003.10196

Two Families of Examples of Groups Acting on Trees with Nontrivial Quasi-Kernels

Nikolay A. Ivanov
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Abstract

We introduce two families of examples of groups acting on trees, one consisting of group amalgamations and the other consisting of HNN-extensions, motivated by the problems of $C^*$-simplicity and unique trace property. Moreover, we prove that our examples are not inner amenable and identify a relatively large, simple, normal subgroup in each one.

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Nikolay A. Ivanov. 2020-03-23. Two Families of Examples of Groups Acting on Trees with Nontrivial Quasi-Kernels. https://arxiv.org/abs/2003.10196

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