Abstract
Let be a free group outer automorphism that can be represented by an expanding, irreducible train-track map. The automorphism determines a free-by-cyclic group and a homomorphism . By work of Neumann, Bieri, Neumann and Strebel, and Dowdall, Kapovich and Leininger, has an open cone neighborhood in whose integral points correspond to other fibrations of whose associated outer automorphisms are themselves representable by expanding irreducible train-track maps. In this paper, we define an analog of McMullen’s Teichmüller polynomial that computes the dilatations of all outer automorphisms in .
Citation
Yael Algom-Kfir. Eriko Hironaka. Kasra Rafi. "Digraphs and cycle polynomials for free-by-cyclic groups." Geom. Topol. 19 (2) 1111 - 1154, 2015. https://doi.org/10.2140/gt.2015.19.1111
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