On curves intersecting at most once, II

Joshua Evan Greene

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arXiv · 1811.01413

On curves intersecting at most once, II

Joshua Evan Greene

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Abstract

We prove that on a closed, orientable surface of genus $g$, a set of simple loops with the property that no two are homotopic or intersect in more than $k$ points has cardinality $\lesssim_k g^{k+1} \log g$. The bound matches the size of the largest known construction to within a factor of $\sim_k \log g$. It generalizes an earlier result of the author, which treated the case $k=1$. The proof blends probabilistic ideas with covering space arguments related to the fact that surface groups are LERF.

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Joshua Evan Greene. 2018-11-04. On curves intersecting at most once, II. https://arxiv.org/abs/1811.01413

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