Pseudo-Anosov subgroups of surface bundles over tori

Junmo Ryang

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arXiv · 2505.07848

Pseudo-Anosov subgroups of surface bundles over tori

Junmo Ryang

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Abstract

We show that finitely generated, purely pseudo-Anosov subgroups of the fundamental groups of surface bundles over tori are convex cocompact as subgroups of the mapping class group via the Birman exact sequence. This generalizes the fact that similar groups within fibered 3-manifold groups are convex cocompact, which is a combination of results due to Dowdall, Kent, Leininger, Russell, and Schleimer.

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Junmo Ryang. 2025-05-07. Pseudo-Anosov subgroups of surface bundles over tori. https://arxiv.org/abs/2505.07848

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