Mapping class group orbits of curves with self-intersections

Patricia Cahn; Federica Fanoni; Bram Petri

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arXiv · 1603.00846

Mapping class group orbits of curves with self-intersections

Patricia Cahn·Federica Fanoni·Bram Petri

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Abstract

We study mapping class group orbits of homotopy and isotopy classes of curves with self-intersections. We exhibit the asymptotics of the number of such orbits of curves with a bounded number of self-intersections, as the complexity of the surface tends to infinity. We also consider the minimal genus of a subsurface that contains the curve. We determine the asymptotic number of orbits of curves with a fixed minimal genus and a bounded self-intersection number, as the complexity of the surface tends to infinity. As a corollary of our methods, we obtain that most curves that are homotopic are also isotopic. Furthermore, using a theorem by Basmajian, we get a bound on the number of mapping class group orbits on a given a hyperbolic surface that can contain short curves. For a fixed length, this bound is polynomial in the signature of the surface. The arguments we use are based on counting embeddings of ribbon graphs.

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BibTeX RIS

Patricia Cahn, Federica Fanoni, Bram Petri. 2016-03-02. Mapping class group orbits of curves with self-intersections. https://arxiv.org/abs/1603.00846

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