Automorphisms of the loop and arc graph of an infinite-type surface

Anschel Schaffer-Cohen

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arXiv · 1912.06774

Automorphisms of the loop and arc graph of an infinite-type surface

Anschel Schaffer-Cohen

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Abstract

We show that the extended based mapping class group of an infinite-type surface is naturally isomorphic to the automorphism group of the loop graph of that surface. Additionally, we show that the extended mapping class group stabilizing a finite set of punctures is isomorphic to the arc graph relative to that finite set of punctures. This extends a known result for sufficiently complex finite-type surfaces, and provides a new angle from which to study the mapping class groups of infinite-type surfaces.

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Anschel Schaffer-Cohen. 2019-12-14. Automorphisms of the loop and arc graph of an infinite-type surface. https://arxiv.org/abs/1912.06774

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