English

Obstructions to choosing distinct points on cubic plane curves

Geometric Topology 2019-02-12 v2 Algebraic Geometry

Abstract

Every smooth cubic plane curve has 9 inflection points, 27 sextatic points, and 72 ``points of type nine". Motivated by these classical algebro-geometric constructions, we study the following topological question: Is it possible to continuously choose nn distinct unordered points on each smooth cubic plane curve for a natural number nn? This question is equivalent to asking if certain fiber bundle admits a continuous section or not. We prove that the answer is no when nn is not a multiple of 9. Our result resolves a conjecture of Benson Farb.

Keywords

Cite

@article{arxiv.1806.10207,
  title  = {Obstructions to choosing distinct points on cubic plane curves},
  author = {Weiyan Chen},
  journal= {arXiv preprint arXiv:1806.10207},
  year   = {2019}
}

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R2 v1 2026-06-23T02:42:49.580Z