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Related papers: Anabelian geometry with etale homotopy types

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Synthetic algebraic geometry uses homotopy type theory extended with three axioms to develop algebraic geometry internal to a higher version of the Zariski topos. In this article we make no essential use of the higher structure and use…

Algebraic Geometry · Mathematics 2025-10-06 Felix Cherubini , Matthias Hutzler , Hugo Moeneclaey , David Wärn

We study hyperbolic curves and their Jacobians over finite fields in the context of anabelian geometry.

Algebraic Geometry · Mathematics 2008-02-27 Fedor Bogomolov , Mikhail Korotiaev , Yuri Tschinkel

For a (semi-)model category M, we define a notion of a ''homotopy'' Grothendieck topology on M, as well as its associated model category of stacks. We use this to define a notion of geometric stack over a symmetric monoidal base model…

Algebraic Geometry · Mathematics 2007-05-23 Bertrand Toen , Gabriele Vezzosi

The pro-\'etale fundamental group of a scheme, introduced by Bhatt and Scholze, generalizes the usual \'etale fundamental group $\pi_1^{\mathrm{et}}$ defined in SGA1 and leads to an interesting class of "geometric coverings" of schemes,…

Algebraic Geometry · Mathematics 2019-11-06 Marcin Lara

Generalized Bott manifolds (over $\mathbb C$ and $\mathbb R$) have been defined by Choi, Masuda and Suh. In this article we extend the results of arXiv:1609.05630 on the topology of real Bott manifolds to generalized real Bott manifolds. We…

Algebraic Topology · Mathematics 2017-10-18 Raisa Dsouza , V Uma

We prove that a certain class of open homomorphisms between Galois groups of function fields of curves over finite fields arise from embeddings between the function fields.

Algebraic Geometry · Mathematics 2009-12-11 Mohamed Saidi , Akio Tamagawa

In this article we study the endomorphism algebras of abelian varieties $A$ defined over a given number field $K$ with large cyclic 2-torsion fields. A key step in doing so is to provide criteria for all the endomorphisms of $A$ to be…

Number Theory · Mathematics 2026-03-24 Pip Goodman

Let $A$ be an abelian variety over an algebraically closed field. We show that $A$ is the automorphism group scheme of some smooth projective variety if and only if $A$ has only finitely many automorphisms as an algebraic group. This…

Algebraic Geometry · Mathematics 2021-05-24 Jérémy Blanc , Michel Brion

Grothendieck gave two forms of his "main conjecture of anabelian geometry", i.e. the section conjecture and the hom conjecture. He stated that these two forms are equivalent and that if they hold for hyperbolic curves then they hold for…

Algebraic Geometry · Mathematics 2021-01-21 Giulio Bresciani

The purpose of this paper is to generalise Sullivan's rational homotopy theory to non-nilpotent spaces, providing an alternative approach to defining Toen's schematic homotopy types over any field k of characteristic zero. New features…

Algebraic Topology · Mathematics 2009-02-04 J. P. Pridham

We study the arithmetic of abelian varieties over $K=k(t)$ where $k$ is an arbitrary field. The main result relates Mordell-Weil groups of certain Jacobians over $K$ to homomorphisms of other Jacobians over $k$. Our methods also yield…

Number Theory · Mathematics 2011-02-21 Douglas Ulmer

A $\nabla$-algebra is a natural generalization of a Heyting algebra, unifying several algebraic structures, including bounded lattices, Heyting algebras, temporal Heyting algebras, and the algebraic representation of dynamic topological…

Logic · Mathematics 2024-09-18 Amirhossein Akbar Tabatabai , Majid Alizadeh , Masoud Memarzadeh

We introduce the category of finite \'etale covers of an arbitrary schematic finite space $X$ and show that, equipped with an appropriate natural fiber functor, it is a Galois Category. This allows us to define the \'etale fundamental group…

Algebraic Geometry · Mathematics 2021-05-06 J. Sánchez González , C. Tejero Prieto

For a certain class of abelian categories, we show how to make sense of the "Euler characteristic" of an infinite projective resolution (or, more generally, certain chain complexes that are only bounded above), by passing to a suitable…

Category Theory · Mathematics 2014-02-26 Pramod N. Achar , Catharina Stroppel

Let ${\cal M}_{g,[n]}$, for $2g-2+n>0$, be the D-M moduli stack of smooth curves of genus $g$ labeled by $n$ unordered distinct points. The main result of the paper is that a finite, connected \'etale cover ${\cal M}^\l$ of ${\cal…

Algebraic Geometry · Mathematics 2023-05-24 M. Boggi , P. Lochak

For any type of fundamental groupoid scheme, we construct an algebraic cohomology theory for varieties with coefficients in the base field. This is a minor variant of \'etale cohomology, involving neither de Rham complexes nor…

Algebraic Geometry · Mathematics 2026-02-16 Hyuk Jun Kweon

We study model geometries of finitely generated groups. If a finitely generated group does not contain a non-trivial finite rank free abelian commensurated subgroup, we show any model geometry is dominated by either a symmetric space of…

Group Theory · Mathematics 2024-09-06 Alex Margolis

This work presents a way to associate a Grothendieck site structure to a category endowed with a unique factorisation system of its arrows. In particular this recovers the Zariski and Etale topologies and others related to Voevodsky's…

Algebraic Geometry · Mathematics 2009-10-22 Mathieu Anel

In this paper, we present some partial results for the geometrically m-step solvable Grothendieck conjecture in anabelian geometry. Among other things, we prove the geometrically 3-step solvable Grothendieck conjecture for genus 0 curves…

Algebraic Geometry · Mathematics 2025-02-18 Naganori Yamaguchi

Let k be a field, and let {\pi}:\tilde{X} -> X be a proper birational morphism of irreducible k-varieties, where \tilde{X} is smooth and X has at worst quotient singularities. When the characteristic of k is zero, a theorem of Koll\'ar in…

Algebraic Geometry · Mathematics 2013-11-26 Indranil Biswas , Amit Hogadi