On the residual finiteness of outer automorphisms of hyperbolic groups
نویسندگان
چکیده
We show that every virtually torsion-free subgroup of the outer automorphism group of a conjugacy separable hyperbolic group is residually finite. As a result, we are able to prove that the group of outer automorphisms of every finitely generated Fuchsian group and of every free-by-finite group is residually finite.
منابع مشابه
O ct 2 00 5 On the residual finiteness of outer automorphisms of relatively hyperbolic groups
We show that every virtually torsion-free subgroup of the outer au-tomorphism group of a conjugacy separable hyperbolic group is residually finite. As a result, we are able to prove that the group of outer automorphisms of every finitely generated Fuchsian group and of every free-by-finite group is residually finite. We also generalise the main result for relatively hyperbolic groups.
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