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arXiv · 2604.18815

The Dehn-Nielsen-Baer Theorem for Bounded Surfaces

Elysia Wang
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Abstract

Let $Σ$ be a bounded surface. We prove the Dehn-Nielsen-Baer theorem for bounded surfaces to show that the mapping class group of $Σ$ is isomorphic to the automorphisms of the fundamental groupoid of $Σ$ that fix loops around the boundary.

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Elysia Wang. 2026-04-20. The Dehn-Nielsen-Baer Theorem for Bounded Surfaces. https://arxiv.org/abs/2604.18815

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