English
Related papers

Related papers: Inverse Galois problem for del Pezzo surfaces over…

200 papers

In this article we prove that the Kawamata-Viehweg vanishing theorem holds for regular del Pezzo surfaces over imperfect ground fields of characteristic $p>3$.

Algebraic Geometry · Mathematics 2020-11-10 Omprokash Das

We construct an infinite family of quartic del Pezzo surfaces over $\mathbb{F}_p(t)$ with no quadratic points, for all primes $p\neq 2$. This answers a question of Colliot--Th\'el\`ene, Creutz and Viray in the negative, which asks whether…

Number Theory · Mathematics 2026-02-26 Giorgio Navone , Katerina Santicola , Harry C. Shaw , Haowen Zhang

In this manuscript, we apply patching methods to give a positive answer to the inverse differential Galois problem over function fields over Laurent series fields of characteristic zero. More precisely, we show that any linear algebraic…

Commutative Algebra · Mathematics 2017-05-17 David Harbater , Julia Hartmann , Annette Maier

We classify geometrically integral regular del Pezzo surfaces which are not geometrically normal over imperfect fields of positive characteristic. Based on this classification, we show that a three-dimensional terminal del Pezzo fibration…

Algebraic Geometry · Mathematics 2025-11-12 Fabio Bernasconi , Hiromu Tanaka

Infinitesimal bendings for classes of two-dimensional surfaces in $\mathbb{R}^3$ are investigated. The techniques used to construct the bending fields include reduction to solvability of Bers-Vekua type equations and systems of differential…

Analysis of PDEs · Mathematics 2021-11-24 B. de Lessa Victor , Abdelhamid Meziani

In this paper we study the classification of del Pezzo surfaces $X$ of degree $5$ over any perfect field $\mathbf{k}$ in explicit geometric terms. More precisely, in each case we use the Petersen graph to illustrate the…

Algebraic Geometry · Mathematics 2026-02-23 Aurore Boitrel

We survey some of the recent works on the geometry of del Pezzo surfaces over imperfect fields, with applications to 3-dimensional del Pezzo fibrations in positive characteristic. We place particular emphasis on cases where the general…

Algebraic Geometry · Mathematics 2024-12-17 Fabio Bernasconi

We characterise integral points of bounded log-anticanonical height on a quartic del Pezzo surface of singularity type $\mathbf{A}_3$ over imaginary quadratic fields with respect to its singularity and its lines. Furthermore, we count these…

Number Theory · Mathematics 2023-07-25 Judith Ortmann

In positive characteristic, nearly all Picard-Vessiot extensions are inseparable over some intermediate iterative differential extensions. In the Galois correspondence, these intermediate fields correspond to nonreduced subgroup schemes of…

Commutative Algebra · Mathematics 2022-01-13 Andreas Maurischat

We compute the complexity of del Pezzo surfaces with du Val singularities.

Algebraic Geometry · Mathematics 2025-04-18 Valentine Nadler

We prove new local inequality for divisors on surfaces and utilize it to compute $\alpha$-invariants of singular del Pezzo surfaces, which implies that del Pezzo surfaces of degree one whose singular points are of type $\mathbb{A}_{1}$,…

Algebraic Geometry · Mathematics 2012-10-04 Ivan Cheltsov , Dimitra Kosta

We study the algebraic Brauer classes on open del Pezzo surfaces of degree $4$. I.e., on the complements of geometrically irreducible hyperplane sections of del Pezzo surfaces of degree $4$. We show that the $2$-torsion part is generated by…

Algebraic Geometry · Mathematics 2019-01-14 Jörg Jahnel , Damaris Schindler

Among geometrically rational surfaces, del Pezzo surfaces of degree two over a field k containing at least one point are arguably the simplest that are not known to be unirational over k. Looking for k-rational curves on these surfaces, we…

Algebraic Geometry · Mathematics 2017-05-17 Cecília Salgado , Damiano Testa , Anthony Várilly-Alvarado

This note presents Galois theory for finite fields. It was written as a handout for the MAT401 course ``Polynomial equations and fields'' taught at the University of Toronto in Spring 2026. We use without proofs some basic properties of…

Number Theory · Mathematics 2026-04-13 Askold Khovanskii

We show how to construct infinite families of explicitly determined cubic number fields whose class group has a subgroup isomorphic to $(\mathbb{Z}/2)^8$ using degree $1$ del Pezzo surfaces. We illustrate the method and provide an example…

Number Theory · Mathematics 2017-08-01 Avinash Kulkarni

We show that strictly convex surfaces expanding by the inverse Gauss curvature flow converge to infinity in finite time. After appropriate rescaling, they converge to spheres. We describe the algorithm to find our main test function.

Differential Geometry · Mathematics 2007-05-23 Oliver C. Schnürer

We construct an example of a field and a del Pezzo surface of degree $2$ over this field without points such that its automorphism group is isomorphic to $\mathrm{PSL}_2(\mathbb{F}_7) \times \mathbb{Z}/2\mathbb{Z},$ which is the largest…

Algebraic Geometry · Mathematics 2025-01-28 Anastasia V. Vikulova

We study del Pezzo surfaces that are quasismooth and well-formed weighted hypersurfaces. In particular, we find all such surfaces whose alpha-invariant of Tian is greater than 2/3.

Algebraic Geometry · Mathematics 2011-12-30 Ivan Cheltsov , Constantin Shramov

This paper introduces a systematic approach towards the inverse problem for arboreal Galois representations of finite index attached to quadratic polynomials. Let $F$ be a field of characteristic $\neq 2$, $f\in F[x]$ be monic and quadratic…

Number Theory · Mathematics 2023-06-05 Andrea Ferraguti , Carlo Pagano , Daniele Casazza

This is an expanded version of our work [AN88], 1988, in Russian. We classify del Pezzo surfaces over C with log terminal singularities of index \le 2. By classification, we understand a description of the intersection graph of all…

Algebraic Geometry · Mathematics 2007-05-23 Valery Alexeev , Viacheslav V. Nikulin