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We study abelian varieties and K3 surfaces with complex multiplication defined over number fields of fixed degree. We show that these varieties fall into finitely many isomorphism classes over an algebraic closure of the field of rational…

Algebraic Geometry · Mathematics 2019-02-20 Martin Orr , Alexei N. Skorobogatov

Enriques surfaces are minimal surfaces of Kodaira dimension $0$ with $b_{2}=10$. If we work with a field of characteristic away from $2$, Enriques surfaces admit double covers which are K3 surfaces. In this paper, we prove the Shafarevich…

Number Theory · Mathematics 2019-11-25 Teppei Takamatsu

We formulate an analogue of the conjecture of Birch and Swinnerton-Dyer for Abelian schemes with everywhere good reduction over higher dimensional bases over finite fields of characteristic $p$. We prove the prime-to-$p$ part conditionally…

Number Theory · Mathematics 2021-07-06 Timo Keller

We prove a dynamical Shafarevich theorem on the finiteness of the set of isomorphism classes of rational maps with fixed degeneracies. More precisely, fix an integer d at least 2 and let K be either a number field or the function field of a…

Algebraic Geometry · Mathematics 2017-05-17 Lucien Szpiro , Lloyd West

This survey discusses hyperbolicity properties of moduli stacks and generalisations of the Shafarevich Hyperbolicity Conjecture to higher dimensions. It concentrates on methods and results that relate moduli theory with recent progress in…

Algebraic Geometry · Mathematics 2011-12-21 Stefan Kebekus

The classical Shafarevich conjecture predicts that the universal cover of a complex smooth projective variety $X$ is holomorphically convex. In this paper, we propose a refinement of this conjecture for varieties defined over the reals. In…

Algebraic Geometry · Mathematics 2026-03-19 Rodolfo Aguilar , Cristhian Garay

The Shafarevich conjecture/problem is about the finiteness of isomorphism classes of a family of varieties defined over a number field with good reduction outside a finite collection of places. For K3 surfaces, such a finiteness result was…

Algebraic Geometry · Mathematics 2026-04-13 Lie Fu , Zhiyuan Li , Teppei Takamatsu , Haitao Zou

We prove the unpolarized Shafarevich conjecture for K3 surfaces: the set of isomorphism classes of K3 surfaces over a fixed number field with good reduction away from a fixed and finite set of places is finite. Our proof is based on the…

Number Theory · Mathematics 2017-05-26 Yiwei She

Given a finite unbranched covering of a nonsingular projective scheme we analyse the morphism between moduli spaces of sheaves induced by pullback. We have a closer look at cyclic coverings and, in particular, at canonical coverings of…

Algebraic Geometry · Mathematics 2013-02-21 Markus Zowislok

Using an alternative notion of good reduction, an analog of the Shafarevich theorem for elliptic curves is proved for morphisms of the projective line over number fields.

Number Theory · Mathematics 2007-05-23 Lucien Szpiro , Thomas J. Tucker

Motivated by Lang-Vojta's conjectures on hyperbolic varieties, we prove a new version of the Shafarevich conjecture in which we establish the finiteness of pointed families of polarized varieties. We then give an arithmetic application to…

Algebraic Geometry · Mathematics 2024-10-10 Ariyan Javanpeykar , Ruiran Sun , Kang Zuo

This article is concerned with the convexity properties of universal covers of projective varieties. We study the relation between the convexity properties of the universal cover of X and the properties of the pullback map sending vector…

Algebraic Geometry · Mathematics 2007-05-23 F. Bogomolov , B. De Oliveira

We describe several explicit examples of simple abelian surfaces over real quadratic fields with real multiplication and everywhere good reduction. These examples provide evidence for the Eichler-Shimura conjecture for Hilbert modular forms…

Number Theory · Mathematics 2017-07-03 Lassina Dembele , Abhinav Kumar

Esnault-Viehweg developed the theory of cyclic branched coverings $\tilde X\to X$ of smooth surfaces providing a very explicit formula for the decomposition of $H^1(\tilde X,\mathbb{C})$ in terms of a resolution of the ramification locus.…

Algebraic Geometry · Mathematics 2020-01-28 E. Artal Bartolo , J. I. Cogolludo-Agustín , Jorge Martín-Morales

We prove, under some mild hypothesis, that an \'etale cover of curves defined over a number field has infinitely many specializations into an everywhere unramified extension of number fields. This constitutes an "absolute" version of the…

Number Theory · Mathematics 2017-09-26 Yuri Bilu , Jean Gillibert

Generalizing the well-known Shafarevich hyperbolicity conjecture, it has been conjectured by Viehweg that a quasi-projective manifold that admits a generically finite morphism to the moduli stack of canonically polarized varieties is…

Algebraic Geometry · Mathematics 2007-07-16 Stefan Kebekus , Sandor J. Kovacs

We prove a finiteness theorem for the first flat cohomology group of finite flat group schemes over integral normal proper varieties over finite fields. As a consequence, we can prove the invariance of the finiteness of the Tate-Shafarevich…

Number Theory · Mathematics 2022-03-14 Timo Keller

This article is devoted to examples of (orbifold) K\"ahler groups from the perspective of the so-called Shafarevich conjecture on holomorphic convexity. It aims at pointing out that every quasi-projective complex manifold with an…

Algebraic Geometry · Mathematics 2016-11-29 Philippe Eyssidieux

We study toroidal compactifications of finite volume complex hyperbolic manifolds. We obtain results on the existence or nonexistence of K\"ahler metrics satisfying certain nonpositive curvature properties on these compactifications.…

Complex Variables · Mathematics 2025-10-14 William Sarem

In this paper, we prove the Shafarevich conjecture for certain complete intersections of hypersurfaces in abelian varieties defined over a number field $K$ using the Lawrence-Venkatesh method. The main new inputs we need are computation of…

Number Theory · Mathematics 2025-06-19 Frank Lu