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arXiv · 1711.07923

Hyperbolic extensions of free groups from atoroidal ping-pong

Caglar Uyanik
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Abstract

We prove that all atoroidal automorphisms of $Out(F_N)$ act on the space of projectivized geodesic currents with generalized north-south dynamics. As an application, we produce new examples of non virtually cyclic, free and purely atoroidal subgroups of $Out(F_N)$ such that the corresponding free group extension is hyperbolic. Moreover, these subgroups are not necessarily convex cocompact.

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Caglar Uyanik. 2017-11-21. Hyperbolic extensions of free groups from atoroidal ping-pong. https://doi.org/10.2140/agt.2019.19.1385

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