English

The enumerative geometry of cubic hypersurfaces: point and line conditions

Algebraic Geometry 2022-01-17 v1

Abstract

In order to count the number of smooth cubic hypersurfaces tangent to a prescribed number of lines and passing through a given number of points, we construct a compactification of their moduli space. We term the latter a 11--\textit{complete variety of cubic hypersurfaces} in analogy to the space of complete quadrics. Paolo Aluffi explored the case of plane cubic curves. Starting from his work, we construct such a space in arbitrary dimension by a sequence of five blow-ups. The counting problem is then reduced to the computation of five Chern classes, climbing the sequence of blow-ups. Computing the last of these is difficult due to the fact that the vector bundle is not given explicitly. Identifying a restriction of this vector bundle, we arrive at the desired numbers in the case of cubic surfaces.

Keywords

Cite

@article{arxiv.2201.05424,
  title  = {The enumerative geometry of cubic hypersurfaces: point and line conditions},
  author = {Mara Belotti and Alessandro Danelon and Claudia Fevola and Andreas Kretschmer},
  journal= {arXiv preprint arXiv:2201.05424},
  year   = {2022}
}

Comments

33 pages, comments welcome!