Bertini's theorem for $F$-rational $F$-pure singularities
Algebraic Geometry
2025-09-30 v2 Commutative Algebra
Abstract
Let be an algebraically closed field of characteristic , and let be a quasi-projective variety that is -rational and -pure. We prove that if is a general hyperplane, then is also -rational and -pure. Of related but independent interest, we present a relationship between the characteristic and index of a -Gorenstein variety with isolated non--regular locus which is -pure but not -regular.
Cite
@article{arxiv.2509.04433,
title = {Bertini's theorem for $F$-rational $F$-pure singularities},
author = {Alessandro De Stefani and Thomas Polstra and Austyn Simpson},
journal= {arXiv preprint arXiv:2509.04433},
year = {2025}
}
Comments
v1: 16 pages, comments welcome v2: major revision. Added Section 3; Lemma 3.1 of v1 has been replaced with Theorem 3.1 and Lemma 4.1; both main theorems are unaffected. 17 pages, comments welcome