Orientable maps and polynomial invariants of free-by-cyclic groups

Spencer Dowdall; Radhika Gupta; Samuel J. Taylor

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arXiv · 2203.12134

Orientable maps and polynomial invariants of free-by-cyclic groups

Spencer Dowdall·Radhika Gupta·Samuel J. Taylor

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Abstract

We relate the McMullen polynomial of a free-by-cyclic group to its Alexander polynomial. To do so, we introduce the notion of an orientable fully irreducible outer automorphism $\varphi$ and use it to characterize when the homological stretch factor of $\varphi$ is equal to its geometric stretch factor.

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Spencer Dowdall, Radhika Gupta, Samuel J. Taylor. 2022-03-23. Orientable maps and polynomial invariants of free-by-cyclic groups. https://arxiv.org/abs/2203.12134

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