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arXiv · 0811.2389

Scott and Swarup's regular neighbourhood as a tree of cylinders

Vincent Guirardel·Gilbert Levitt
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Abstract

Let G be a finitely presented group. Scott and Swarup have constructed a canonical splitting of G which encloses all almost invariant sets over virtually polycyclic subgroups of a given length. We give an alternative construction of this regular neighbourhood, by showing that it is the tree of cylinders of a JSJ splitting.

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Vincent Guirardel, Gilbert Levitt. 2008-11-14. Scott and Swarup's regular neighbourhood as a tree of cylinders. https://arxiv.org/abs/0811.2389

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