Category Archives: hyperbolicity of complexes

An even shorter proof that curve graphs are hyperbolic

Posted on September 20, 2013 by Alex Sisto

In this post I described the Hensel-Przytycki-Webb proof that curve graphs are (uniformly) hyperbolic. Their methods actually apply to the arc graph, and then they used a clever evil trick due to Harer that involves adding an artificial puncture to … Continue reading →

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Hyperbolicity of the curve graph: the proof from The Book

Posted on February 8, 2013 by Alex Sisto

In this post I’ll talk about a lovely paper by Sebastian Hensel, Piotr Przytycki and Richard Webb. They show that all curve graphs are 17-hyperbolic. Hyperbolicity of curve graphs is a very very very useful* property because mapping class groups … Continue reading →

Posted in guessing geodesics, hyperbolicity of complexes | 3 Comments