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arXiv · 0911.3173

JSJ decompositions: definitions, existence, uniqueness. I: The JSJ deformation space

Vincent Guirardel·Gilbert Levitt
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Abstract

This paper and its companion arXiv:1002.4564 have been replaced by arXiv:1602.05139. We give a general simple definition of JSJ decompositions by means of a universal maximality property. The JSJ decomposition should not be viewed as a tree (which is not uniquely defined) but as a canonical deformation space of trees. We prove that JSJ decompositions of finitely presented groups always exist, without any assumption on edge groups. Many examples are given.

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Vincent Guirardel, Gilbert Levitt. 2009-11-16. JSJ decompositions: definitions, existence, uniqueness. I: The JSJ deformation space. https://arxiv.org/abs/0911.3173

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