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Limits of (certain) CAT(0) groups, II: The Hopf property and the shortening argument

Daniel Groves
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Abstract

This is the second in a series of papers about torsion-free groups which act properly and cocompactly on a CAT(0) metric space with isolated flats and relatively thin triangles. Our approach is to adapt the methods of Sela and others for word-hyperbolic groups to this context of non-positive curvature. The main result in this paper is that (under certain technical hypotheses) such a group as above is Hopfian. This (mostly) answers a question of Sela.

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Daniel Groves. 2004-08-05. Limits of (certain) CAT(0) groups, II: The Hopf property and the shortening argument. https://arxiv.org/abs/math/0408080

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