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Quasi-isometries between groups with infinitely many ends

Panos Papazoglu·Kevin Whyte
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Abstract

Let G and F be finitely generated groups with infinitely many ends and let A and B be graph of groups decompositions of F and G such that all edge groups are finite and all vertex groups have at most one end. We show that G and F are quasi-isometric if and only if every one-ended vertex group of A is quasi-isometric to some one-ended vertex group of B and every one-ended vertex group of B is quasi-isometric to some one-ended vertex group of A. From our proof it also follows that if G is any finitely generated group, of order at least three, the groups: G*G, G*Z,G*G*G and G* Z/2Z are all quasi-isometric.

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Panos Papazoglu, Kevin Whyte. 2004-05-14. Quasi-isometries between groups with infinitely many ends. https://arxiv.org/abs/math/0405274

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