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arXiv · 2508.21264

Asymptotically rigid mapping class groups of infinite graphs

Thomas Hill·Sanghoon Kwak·Brian Udall·Jeremy West
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Abstract

We introduce and study asymptotically rigid mapping class groups of certain infinite graphs. We determine their finiteness properties and show that these depend on the number of ends of the underlying graph. In a special case where the graph has finitely many ends, we construct an explicit presentation for the so-called pure graph Houghton group and investigate several of its algebraic and geometric properties. Additionally, we show that the graph Houghton groups are not commensurable with other known Houghton-type groups, namely the classical, surface, braided, handlebody, and doubled handlebody Houghton groups, demonstrating that this graph-based construction defines a genuinely new class of groups.

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Thomas Hill, Sanghoon Kwak, Brian Udall, Jeremy West. 2025-08-28. Asymptotically rigid mapping class groups of infinite graphs. https://arxiv.org/abs/2508.21264

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