The bicorn curves on closed surfaces

Takuya Katayama; Erika Kuno

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arXiv · 2512.10306

The bicorn curves on closed surfaces

Takuya Katayama·Erika Kuno

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Abstract

This paper focuses on using the theory of bicorn curves in the context of closed surfaces to understand hyperbolic phenomena of the curve graphs of those surfaces. We prove that the curve graph of any closed surface is 15-hyperbolic with one exception. Furthermore, we provide significantly tighter bounds for the bounded geodesic image theorem, originally proven by Masur--Minsky.

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BibTeX RIS

Takuya Katayama, Erika Kuno. 2025-12-11. The bicorn curves on closed surfaces. https://arxiv.org/abs/2512.10306

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