English
Related papers

Related papers: Good Reduction of K3 Surfaces

200 papers

For a wildly ramified extension $K/k$ of complete discrete valuation fields we study collections of elements of $k[G]$ (where $G=Gal(K/k)$) that fit well for constructing bases of various associated Galois modules and orders. In the case…

Algebraic Geometry · Mathematics 2026-05-22 Mikhail V. Bondarko , Kirill S. Ladny , Konstantin I. Pimenov

The theory of p-ramification, regarding the Galois group of the maximal pro-p-extension of a number field K, unramified outside p and $\infty$, is well known including numerical experiments with PARI/GP programs. The case of ``incomplete…

Number Theory · Mathematics 2021-08-06 Georges Gras

In this paper, we explore different possible choices of expanded degenerations and define appropriate stability conditions in order to construct good degenerations of Hilbert schemes of points over semistable degenerations of surfaces,…

Algebraic Geometry · Mathematics 2024-02-16 Calla Tschanz

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 study Galois covers of the projective line branched at three points with bad reduction to characteristic p, under the condition that p exactly divides the order of the Galois group. As an application of our results, we prove that the…

Algebraic Geometry · Mathematics 2007-05-23 Stefan Wewers

In this paper we prove the Mumford-Tate conjecture in degree 2 for the product of an abelian surface $A$ and a K3 surface $X$ over a finitely generated field $K \subset \mathbb{C}$. The Mumford-Tate conjecture is a precise way of saying…

Algebraic Geometry · Mathematics 2017-09-11 Johan Commelin

For a field F with discrete valuation and residue field $k$ we relate the third homology of SL_2(F) with half-integral coefficients to the third homology of SL_2(k) and a certain refined scissors congruence group of k. As an application, we…

K-Theory and Homology · Mathematics 2016-05-24 Kevin Hutchinson

By a lattice theoretic approach, Brandhorst--Hashimoto has made the list of K3 surfaces with finite groups of automorphisms which properly contain a maximal symplectic automorphism group. We give $3$ different explicit descriptions to the…

Algebraic Geometry · Mathematics 2026-02-24 Hayato Nukui

We continue the examination of the stable reduction and fields of moduli of G-Galois covers of the projective line over a complete discrete valuation field of mixed characteristic (0, p), where G has a cyclic p-Sylow subgroup P of order…

Algebraic Geometry · Mathematics 2015-03-03 Andrew Obus

Let $E$ be an elliptic curve over an imaginary quadratic field $K$, and $p$ be an odd prime such that the residual representation $E[p]$ is reducible. The $\mu$-invariant of the fine Selmer group of $E$ over the anticyclotomic…

Number Theory · Mathematics 2022-02-24 Debanjana Kundu , Anwesh Ray

In this note we present the classification of non-symplectic automorphisms of prime order on K3 surfaces, i.e.we describe the topological structure of their fixed locus and determine the invariant lattice in cohomology. We provide new…

Algebraic Geometry · Mathematics 2010-01-27 Michela Artebani , Alessandra Sarti , Shingo Taki

Let $K/\mathbb{Q}$ be a finitely generated field of characteristic zero and $X/K$ a smooth projective variety. Fix $q\in\mathbb{N}$. For every prime number $\ell$ let $\rho_\ell$ be the representation of $\mathrm{Gal}(K)$ on the \'etale…

Algebraic Geometry · Mathematics 2017-01-18 Sebastian Petersen

We determine the Galois representations inside the $l$-adic cohomology of some quaternionic and related unitary Shimura varieties at ramified places. The main results generalize the previous works of Reimann and Kottwitz in this setting to…

Number Theory · Mathematics 2019-02-20 Xu Shen

This article is a survey of conjectures and results on reductive algebraic groups having good reduction at a suitable set of discrete valuations of the base field. Until recently, this subject has received relatively little attention, but…

Number Theory · Mathematics 2020-08-18 Andrei S. Rapinchuk , Igor A. Rapinchuk

Continuing the research initiated in \cite{Fr-Ki2}, we study the existence of solutions and their regularity for the cohomological equations $X u=f$ for locally Hamiltonian flows (determined by the vector field $X$) on a compact surface $M$…

Dynamical Systems · Mathematics 2025-09-25 Krzysztof Frączek , Minsung Kim

We prove a local-global principle for the embedding problems of global fields with restricted ramification. By this local-global principle, for a global field $k$, we use only the local information to give a presentation of the maximal…

Number Theory · Mathematics 2022-12-21 Yuan Liu

We study stable rationality of conic bundles $X$ over $\mathbb{P}^1$ defined over non-closed field $k$ via the cohomology of the Galois group of finite field extension $k'/k$ with action on the geometric Picard lattice of $X$.

Algebraic Geometry · Mathematics 2024-12-24 Kaiqi Yang

Let $K$ be the function field of a smooth projective geometrically integral curve over a finite extension of $\mathbb{Q}_p$. Following the works of Harari, Scheiderer, Szamuely, Izquierdo, and Tian, we study the local-global and weak…

Number Theory · Mathematics 2024-02-21 Nguyen Manh Linh

Given a field $k$ of characteristic zero and an indeterminate $T$ over $k$, we investigate the local behaviour at primes of $k$ of finite Galois extensions of $k$ arising as specializations of finite Galois extensions $E/k(T)$ (with $E/k$…

Number Theory · Mathematics 2018-01-08 Joachim König , François Legrand , Danny Neftin

We prove a version of Temkin's local altered uniformization theorem. We show that for any rig-smooth, quasi-compact and quasi-separated admissible formal $\mathcal{O}_K$-model $\mathfrak{X}$, there is a finite extension $K'/K$ such that…

Algebraic Geometry · Mathematics 2022-06-14 Bogdan Zavyalov