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arXiv · 0806.4975

Growth of intersection numbers for free group automorphisms

Jason Behrstock·Mladen Bestvina·Matt Clay
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Abstract

For a fully irreducible automorphism ϕof the free group F_k we compute the asymptotics of the intersection number n \mapsto i(T,T'ϕ^n) for trees T,T' in Outer space. We also obtain qualitative information about the geometry of the Guirardel core for the trees T and T'ϕ^n for n large.

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Jason Behrstock, Mladen Bestvina, Matt Clay. 2009-04-27. Growth of intersection numbers for free group automorphisms. https://doi.org/10.1112/jtopol%2Fjtq008

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