Amenability of linear-activity automaton groups
نویسندگان
چکیده
We prove that every linear-activity automaton group is amenable. The proof is based on showing that a sufficiently symmetric random walk on a specially constructed degree 1 automaton group — the mother group — has asymptotic entropy 0. Our result answers an open question by Nekrashevich in the Kourovka notebook, and gives a partial answer to a question of Sidki. Figure 1: A Schreier graph for a linear-activity group
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تاریخ انتشار 2009