English

Obrifold del Pezzo surfaces in $\mathbb P^1 \times \mathbb P^1\times \mathbb P^1$ format

Algebraic Geometry 2025-06-26 v2

Abstract

We construct two types of wellformed and quasismooth biregular models (infinite series) of rigid orbifold del Pezzo surfaces having their (sub) anti-canonical embeddings in P6(wi)\mathbb P^6(w_i) . One type of model contains a family of rigid del Pezzo surfaces with a fixed Fano index and weights of ambient P6(wi)\mathbb P^6(w_i) are parameterized by positive integers. In the other type of models, weights of P6(wi)\mathbb P^6(w_i) and Fano index, both are parameterized by the positive integers. The equations describing their images under (sub) anti-canonical embeddings are given in terms of the equations of the Segre embedding of P1×P1×P1\mathbb P^1 \times \mathbb P^1\times \mathbb P^1, which has codimension 4 in P7\mathbb P^7. We also give a formula for the Hilbert series of a generic weighted P1×P1×P1\mathbb P^1 \times \mathbb P^1\times \mathbb P^1 variety, a key tool in these constructions.

Keywords

Cite

@article{arxiv.2312.17339,
  title  = {Obrifold del Pezzo surfaces in $\mathbb P^1 \times \mathbb P^1\times \mathbb P^1$ format},
  author = {Muhammad Imran Qureshi},
  journal= {arXiv preprint arXiv:2312.17339},
  year   = {2025}
}

Comments

17 pages, 3 tables, Final version, Accepted at Exp. Math