English

A four-dimensional cousin of the Segre cubic

Algebraic Geometry 2022-11-30 v1

Abstract

This note is devoted to a special Fano fourfold defined by a four-dimensional space of skew-symmetric forms in five variables. This fourfold appears to be closely related with the classical Segre cubic and its Cremona-Richmond configuration of planes. Among other exceptional properties, it is infinitesimally rigid and has Picard number six. We show how to construct it by blow-up and contraction, starting from a configuration of five planes in a four-dimensional quadric, compatibly with the symmetry group S5S_5. From this construction we are able to describe the Chow ring explicitly.

Keywords

Cite

@article{arxiv.2211.16154,
  title  = {A four-dimensional cousin of the Segre cubic},
  author = {Laurent Manivel},
  journal= {arXiv preprint arXiv:2211.16154},
  year   = {2022}
}