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Related papers: Weak toroidalization over non-closed fields

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We give a short proof of Macintyre's Theorem on Quantifier Elimination for the p-adic numbers, using a version of monomialization that follows directly from the Weak Toroidalization Theorem of Abramovich an Karu (extended to non-closed…

Algebraic Geometry · Mathematics 2011-09-01 Jan Denef

We give a simplified algorithm of the functorial weak factorization of birational morphisms of nonsingular varieties over a field of characteristic zero into a composite of blow-ups and blow-downs with smooth centers.

Algebraic Geometry · Mathematics 2007-05-23 Jaroslaw Wlodarczyk

In this paper we prove strong toroidalization of birational morphisms of 3-folds. Suppose that f:X\to Y is a birational morphism of nonsingular complete 3-folds, and D_Y, D_X are simple normal crossings divisors on Y and X such that…

Algebraic Geometry · Mathematics 2007-05-23 Steven Dale Cutkosky

We show that saturated base change of a dominant toroidal morphism is also toroidal. For completeness, we give full details on equivalence between definitions regarding toroidal embeddings and toroidal morphisms in literature. Moreover, we…

Algebraic Geometry · Mathematics 2025-09-22 Santai Qu

We prove that a quasi-finite endomorphism of an algebraic variety over an algebraically closed field of characteristic zero, that is injective on the complement of a closed subvariety, is an automorphism. We also prove that an endomorphism…

Algebraic Geometry · Mathematics 2021-04-02 Nilkantha Das

We provide a new proof of the following result: Let $X$ be a variety of finite type over an algebraically closed field $k$ of characteristic 0, let $Z\subset X$ be a proper closed subset. There exists a modification $f:X_1 \rar X$, such…

alg-geom · Mathematics 2015-06-30 Dan Abramovich , Johan de Jong

We introduce horizontal and vertical motivic invariants of birational maps between rational dominant maps and study their basic properties. As a first application, we show that the (usual) motivic invariants vanish for birational…

Algebraic Geometry · Mathematics 2026-01-19 Hsueh-Yung Lin , Evgeny Shinder

We prove functorial weak factorization of projective birational morphisms of regular quasi-excellent schemes in characteristic 0 broadly based on the existing line of proof for varieties. From this general functorial statement we deduce…

Algebraic Geometry · Mathematics 2019-03-27 Dan Abramovich , Michael Temkin

Let $K$ be an algebraically closed field of arbitrary characteristic and let $X$ be an irreducible projective variety over $K$. Let $G\subseteq\text{Bir}(X)$ be a bounded-degree subgroup. We prove that there exists an irreducible projective…

Algebraic Geometry · Mathematics 2024-03-13 She Yang

We give evidence for a uniformization-type conjecture, that any algebraic variety can be altered into a variety endowed with a tower of smooth fibrations of relative dimension one.

Algebraic Geometry · Mathematics 2017-02-01 Federico Buonerba , Fedor Bogomolov

Given an ideal $\mathcal I$ on a variety $X$ with toroidal singularities, we produce a modification $X' \to X$, functorial for toroidal morphisms, making the ideal monomial on a toroidal stack $X'$. We do this by adapting the methods of…

Algebraic Geometry · Mathematics 2017-09-12 Dan Abramovich , Michael Temkin , Jarosław Włodarczyk

We show that every affine or projective algebraic variety defined over the field of real or complex numbers is homeomorphic to a variety defined over the field of algebraic numbers. We construct such a homeomorphism by choosing a small…

Algebraic Geometry · Mathematics 2019-12-03 Adam Parusinski , Guillaume Rond

We establish a structure theorem for the connected automorphism groups of smooth complete toroidal horospherical varieties, that is, toric fibrations over rational homogeneous spaces. The key ingredient is a characterization of the Demazure…

Algebraic Geometry · Mathematics 2026-03-10 Lorenzo Barban , DongSeon Hwang , Minseong Kwon

We study the structure of the Mordell--Weil groups of semiabelian varieties over large algebraic extensions of a finitely generated field of characteristic zero. We consider two types of algebraic extensions in this paper; one is of…

Number Theory · Mathematics 2025-11-27 Takuya Asayama , Yuichiro Taguchi

The algebraic cobordism group of a scheme is generated by cycles that are proper morphisms from smooth quasiprojective varieties. We prove that over a field of characteristic zero the quasiprojectivity assumption can be omitted to get the…

Algebraic Geometry · Mathematics 2013-04-01 José Luis González , Kalle Karu

We consider the set of forms of a toric variety over an arbitrary field: those varieties which become isomorphic to a toric variety after base field extension. In contrast to most previous work, we also consider arbitrary isomorphisms…

Algebraic Geometry · Mathematics 2016-10-04 Alexander Duncan

In this article, we show that a flat morphism of $k$-varieties ($\mathop{\mathrm{char}} k=0$) with locally constant geometric fibers becomes finite \'etale after reduction. When $k$ is a real closed field, we prove that such a morphism…

Algebraic Geometry · Mathematics 2025-03-05 Rizeng Chen

In this short note, we will show the following weak evidence of S. Lang conjecture over function fields. Let f : X ---> Y be a projective and surjective morphism of algebraic varieties over an algebraically closed field k of characteristic…

alg-geom · Mathematics 2008-02-03 Atsushi Moriwaki

In this paper we consider birational properties of ramification in excellent local rings. We give an example showing that local monomialization (and weak local monomialization) can fail for extensions of algebraic local rings in algebraic…

Algebraic Geometry · Mathematics 2015-08-11 Steven Dale Cutkosky

The recent two proofs for the (weak) factorization theorem for birational maps, one by W{\l}odarczyk and the other by Abramovich-Karu-Matsuki-W{\l}odarczyk rely on the results of Morelli. The former uses the process for…

Algebraic Geometry · Mathematics 2007-05-23 D. Abramovich , K. Matsuki , S. Rashid