2 5 Fe b 20 07 Generic groups acting on regular trees
نویسندگان
چکیده
Let T be a k-regular tree (k ≥ 3) and A = Aut(T) its automorphism group. We analyze a generic finitely generated subgroup Γ of A. We show that Γ is free and establish a trichotomy on the closure Γ of Γ in A. It turns out that Γ is either discrete, compact or has index at most 2 in A.
منابع مشابه
Generic Groups Acting on Regular Trees
Let T be a k-regular tree (k ≥ 3) and A = Aut(T ) its automorphism group. We analyze a generic finitely generated subgroup Γ of A. We show that Γ is free and establish a trichotomy on the closure Γ of Γ in A. It turns out that Γ is either discrete, compact or has index at most 2 in A.
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