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arXiv · 2211.08923

The dimension of Thurston's spine

Maxime Fortier Bourque
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Abstract

We show that for every $\varepsilon>0$, there exists some $g\geq 2$ such that the set of closed hyperbolic surfaces of genus $g$ whose systoles fill has dimension at least $(5-\varepsilon) g$. In particular, the dimension of this set -- proposed as a spine for moduli space by Thurston -- is larger than the virtual cohomological dimension of the mapping class group.

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Maxime Fortier Bourque. 2022-11-16. The dimension of Thurston's spine. https://doi.org/10.1093/imrn%2Frnad211

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