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arXiv · 0903.0945

Elementary embeddings in torsion-free hyperbolic groups

Chloé Perin
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Abstract

We consider embeddings in a torsion-free hyperbolic group which are elementary in the sense of first-order logic. We give a description of these embeddings in terms of Sela's hyperbolic towers. We deduce as a corollary that subgroups elementarily embedded in finitely generated free groups are free factors.

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Chloé Perin. 2009-03-05. Elementary embeddings in torsion-free hyperbolic groups. https://arxiv.org/abs/0903.0945

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