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arXiv · 1909.03097

Some new CAT(0) free-by-cyclic groups

Rylee Alanza Lyman
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Abstract

We show the existence of several new infinite families of polynomially-growing automorphisms of free groups whose mapping tori are CAT(0) free-by-cyclic groups. Such mapping tori are thick, and thus not relatively hyperbolic. These are the first families comprising infinitely many examples for each rank of the nonabelian free group; they contrast strongly with Gersten's example of a thick free-by-cyclic group which cannot be a subgroup of a CAT(0) group.

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Rylee Alanza Lyman. 2019-09-06. Some new CAT(0) free-by-cyclic groups. https://doi.org/10.1307/mmj/20205989

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