Acylindrical accessibility for groups acting on R-trees
نویسندگان
چکیده
We prove an acylindrical accessibility theorem for finitely generated groups acting on R-trees. Namely, we show that if G is a freely indecomposable non-cyclic k-generated group acting minimally and M-acylindrically on an R-tree X then for any ǫ > 0 there is a finite subtree Yǫ ⊆ X of measure at most 2M (k − 1) + ǫ such that GYǫ = X. This generalizes theorems of Z.Sela and T.Delzant about actions on simplicial trees.
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A ug 2 00 4 ACYLINDRICAL ACCESSIBILITY FOR GROUPS ACTING ON R - TREES
We prove an acylindrical accessibility theorem for finitely generated groups acting on R-trees. Namely, we show that if G is a freely indecomposable non-cyclic k-generated group acting minimally and D-acylindrically on an R-tree X then there is a finite subtree Tε ⊆ X of measure at most 2D(k − 1) + ε such that GTε = X. This generalizes theorems of Z. Sela and T. Delzant about actions on simplic...
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