DISTORTION AND l 1 - HOMOLOGY
نویسنده
چکیده
If H is a finitely generated subgroup of the finitely generated group G, then H is undistorted in G for their word metrics iff the induced homomorphism on the zero-dimensional l1-homology group is injective. The Mayer-Vietoris exact sequence for l1-homology is established and applications are given to hyperbolic groups and relative hyperbolicity. The notion of relative distortion of two maps is introduced and a homological criterion for it is established. §
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