English

Terminal Fano four folds in low codimension

Algebraic Geometry 2025-06-30 v1

Abstract

We construct well-formed and quasismooth terminal Fano 4-folds of index 1 in low codimension containing at worst isolated orbifold points. We provide a certain classification of these varieties where their images under the anitcanonical embedding can be described as codimension 2, 3, or 4 subvarieties of some weighted projective space. In particular, we focus on isolated terminal Fano 4-folds that either have an empty linear system or a relatively large one, but whose linear section is not an isolated canonical Calabi--Yau 3-fold. In total, we classify 95 families of terminal Fano 4-folds of the first type and 32 families of the second type. We also describe our algorithmic approach and the pivotal role of computer algebra in our results.

Keywords

Cite

@article{arxiv.2506.21958,
  title  = {Terminal Fano four folds in low codimension},
  author = {Muhammad Imran Qureshi},
  journal= {arXiv preprint arXiv:2506.21958},
  year   = {2025}
}

Comments

16 pages, 4 Tables, to appear in the proceedings of ISSAC25