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Related papers: Kobayashi-Ochiai's theorem for log schemes

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Kobayashi-Ochiai proved that the set of dominant maps from a fixed variety to a fixed variety of general type is finite. We prove the natural extension of their finiteness theorem to Campana's orbifold pairs.

Algebraic Geometry · Mathematics 2023-08-03 Finn Bartsch , Ariyan Javanpeykar

The dominant rational maps of finite degree from a fixed variety to varieties of general type, up to birational isomorphisms, form a finite set. This has been known as the Iitaka-Severi conjecture, and is nowdays an established result, in…

Algebraic Geometry · Mathematics 2009-04-09 Lucio Guerra , Gian Pietro Pirola

We prove a finiteness result for dominant rational maps whose orbifold base is of general type. Our finiteness result generalizes Maehara's theorem that a given variety dominates only finitely many projective varieties of general type up to…

Algebraic Geometry · Mathematics 2026-04-01 Finn Bartsch , Ariyan Javanpeykar , Erwan Rousseau

Motivated by Lang-Vojta's conjecture, we show that the set of dominant rational self-maps of an algebraic variety over a number field with only finitely many rational points in any given number field is finite by combining Amerik's theorem…

Algebraic Geometry · Mathematics 2020-06-17 Ariyan Javanpeykar , Junyi Xie

Let $k$ be an algebraically closed field. Chambert-Loir proved that the \'etale fundamental group of a normal rationally chain connected variety over $k$ is finite. We prove that the fundamental group scheme of a normal rationally chain…

Algebraic Geometry · Mathematics 2015-05-22 Marco Antei , Indranil Biswas

We extend the theory of decomposable maps by giving a detailed description of k-positive maps. A relation between transposition and modular theory is established. The structure of positive maps in terms of modular theory (the generalized…

Mathematical Physics · Physics 2016-09-07 Louis E. Labuschagne , Władysław A. Majewski , Marcin Marciniak

A theorem due to Ohkawa states that the collection of Bousfield equivalence classes of spectra is a set. We extend this result to arbitrary combinatorial model categories.

Algebraic Topology · Mathematics 2014-05-28 Carles Casacuberta , Javier J. Gutiérrez , Jirí Rosický

We prove the following generalization of Severi's Theorem: Let $X$ be a fixed complex variety. Then there exist, up to birational equivalence, only finitely many complex varieties $Y$ of general type of dimension at most three which admit a…

alg-geom · Mathematics 2014-12-02 Gerd Dethloff

We introduce a notion of proper morphism for schematic finite spaces and prove the analogue of Grothendieck's finiteness theorem for it by means of the classic result for schemes and general descent arguments. This result also generalizes…

Algebraic Geometry · Mathematics 2023-05-22 Javier Sánchez González

We characterise when the log arc scheme of a fine log scheme $(X, M)$, with $X$ a variety over a field of characteristic zero, is irreducible. This generalises the theorem of Kolchin that the (ordinary) arc scheme of $X$ is irreducible…

Algebraic Geometry · Mathematics 2014-04-22 Balin Fleming

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

In the present paper, we prove the existence of universal polynomials which express multi-singularity loci classes of prescribed types for proper morphisms between smooth schemes over an algebraically closed field of characteristic zero --…

Algebraic Geometry · Mathematics 2024-06-19 Toru Ohmoto

We define the generalized logarithmic Gauss map for algebraic varieties of the complex algebraic torus of any codimension. Moreover, we describe the set of critical points of the logarithmic mapping restricted to our variety, and we show an…

Algebraic Geometry · Mathematics 2012-05-15 Farid Madani , Mounir Nisse

This work is dedicated to the construction of a new motivic homotopy theory for (log) schemes, generalizing Morel-Voevodsky's (un)stable $\mathbb{A}^1$-homotopy category. Our framework can be used to represent log topological Hochschild and…

Algebraic Geometry · Mathematics 2025-07-03 Federico Binda , Doosung Park , Paul Arne Østvær

Our goal in this note is to show that cohomology classes with coefficients in finite flat group schemes can be killed by finite covers of the base scheme, and similarly for abelian schemes with "finite covers" replaced by "proper covers."…

Algebraic Geometry · Mathematics 2011-09-13 Bhargav Bhatt

Our main theorem is an extension of the well-known Mizoguchi-Takahaashi's fixed point theorem [N. Mizogochi and W. Takahashi, Fixed point theorems for multi-valued mappings on complete metric space, {\it J. Math. Anal. Appl.} 141 (1989)…

Metric Geometry · Mathematics 2010-01-08 M. Eshaghi Gordji , H. Baghani , M. Ramezani , H. Khodaei

We generalize Gaeta's Theorem to the family of determinantal schemes. In other words, we show that the schemes defined by minors of a fixed size of a matrix with polynomial entries belong to the same G-biliaison class of a complete…

Algebraic Geometry · Mathematics 2014-01-14 Elisa Gorla

Let X be a projective variety which is covered by a family of rational curves of minimal degree. The classic bend-and-break argument of Mori asserts that if x and y are two general points, then there are at most finitely many curves in that…

Algebraic Geometry · Mathematics 2007-05-23 Stefan Kebekus

We develop a theory of motives with compact support for logarithmic schemes over a field. Starting from the notion of finite logarithmic correspondences with compact support, we define the logarithmic motive with compact support analogous…

Algebraic Geometry · Mathematics 2024-03-26 Nikolai Opdan

We prove the finiteness of the kernel of the localization map in the Galois cohomology of a connected reductive group over a global field

Number Theory · Mathematics 2023-09-22 Dylon Chow
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