Amenability of Universal 2-grigorchuk Group
نویسنده
چکیده
We consider the universal Grigorchuk 2-group, i.e., the group such that every Grigorchuk 2-group is a quotient. We show that this group has a nice universal representation in the group of all functions Func({0, 1, 2}N, Aut(T2)), where T2 is a group of automorphism of the binary tree. Finally, we prove that this universal Grigorchuk 2-group is amenable. The proof is an application of the “Munchhausen trick” developed by V. Kaimanovich.
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