Long turns, INP’s and indices for free group automorphisms

2015/01/01 by Thierry Coulbois, Martin Lustig · 2 citations
Mathematics · #Advanced Algebra and Geometry #Geometric and Algebraic Topology #Homotopy and Cohomology in Algebraic Topology

paper · pdf · doi:10.1215/ijm/1488186022

crossref issued 2015/01/01 · crossref published 2015/01/01 · crossref published-print 2015/01/01 · openalex publication_date 2015/01/01 · crossref created 2019/02/26 · crossref deposited 2024/01/30 · openalex created_date 2025/10/10 · crossref indexed 2026/07/30 · openalex updated_date 2026/07/31

Abstract

The goal of this paper is to introduce a new tool, called 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.

Cited by

• Train track maps for graphs of groups
• Tree substitutions and Rauzy fractals

Related

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• The Recognition Theorem for Out(F_n)
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