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arXiv · 1506.04532

Long turns, INP's and index for free group automorphisms

Thierry Coulbois·Martin Lustig
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Abstract

The goal of this paper is to introduce a new tool, called {\em long turns}, which is a useful addition to the train track technology for automorphisms of free groups, in that it allows one to control periodic INPs in a train track map and hence the index of the induced automorphism.

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Thierry Coulbois, Martin Lustig. 2015-06-15. Long turns, INP's and index for free group automorphisms. https://arxiv.org/abs/1506.04532

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