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

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In this paper, we give the rigidity theorem for a log morphism as an extension of a fixed scheme morphism. We also give several applications of the rigidity theorem.

Algebraic Geometry · Mathematics 2007-05-23 Atsushi Moriwaki

We prove a Ramsey theorem for finite sets equipped with a partial order and a fixed number of linear orders extending the partial order. This is a common generalization of two recent Ramsey theorems due to Soki\'c. As a bonus, our proof…

Combinatorics · Mathematics 2015-02-17 Slawomir Solecki , Min Zhao

Takahasi's theorem on chains of subgroups of bounded rank in a free group is generalized to several classes of semigroups. As an application, it is proved that the subsemigroups of periodic points are finitely generated and periodic orbits…

Group Theory · Mathematics 2015-04-02 Mário J. J. Branco , Gracinda M. S. Gomes , Pedro V. Silva

In this work we develop a theory of motives for logarithmic schemes over fields in the sense of Fontaine, Illusie, and Kato. Our construction is based on the notion of finite log correspondences, the dividing Nisnevich topology on log…

Algebraic Geometry · Mathematics 2021-09-24 Federico Binda , Doosung Park , Paul Arne Østvær

We introduce a new fundamental group scheme for varieties defined over an algebraically closed field of positive characteristic and we use it to study generalization of some of C. Simpson's results to positive characteristic. We also study…

Algebraic Geometry · Mathematics 2015-03-24 Adrian Langer

We establish a fixed-point theorem for the face maps that consist in deleting the $i$th entry of an ordered set. Furthermore, we show that there exists random finite sets of integers that are almost invariant under such deletions.…

Group Theory · Mathematics 2026-04-01 Tom Hutchcroft , Nicolas Monod , Omer Tamuz

Kobayashi introduced a uniform notion of compressibility of infinite binary sequences in terms of relative Turing computations with sub-identity use of the oracle. Kobayashi compressibility has remained a relatively obscure notion, with the…

Computational Complexity · Computer Science 2017-02-28 George Barmpalias , Rodney G. Downey

In this article we give the definitions of log Fano varieties and log Calabi-Yau varieties in the framework of theory of log schemes of Fontain-Illusie-Kato and give congruences of the cardinalities of rational points of them over the log…

Algebraic Geometry · Mathematics 2019-02-04 Yukiyoshi Nakkajima

L\"uroth's theorem describes the dominant maps from rational curves over a field. In this note we study those dominant rational maps from cartesian powers $X^{\Psi}$ of geometrically irreducible varieties $X$ over a field $k$ for infinite…

Algebraic Geometry · Mathematics 2025-11-20 M. Rovinsky

Noguchi proved that the set of dominant maps from a fixed variety to a fixed hyperbolic variety is finite. We extend this result to the setting of orbifold pairs, as introduced by Campana, under suitable assumptions. Certain compactness…

Algebraic Geometry · Mathematics 2024-10-23 Laurine Weibel

If $R$ is a rational map, the Main Result is a uniformization Theorem for the space of decompositions of the iterates of $R$. Secondly, we show that Fatou conjecture holds for decomposable rational maps.

Dynamical Systems · Mathematics 2011-07-01 Carlos Cabrera , Peter Makienko

Every partition of [[omega_1]^{< omega}]^2 into finitely many pieces has a cofinal homogeneous set. Furthermore, it is consistent that every directed partially ordered set satisfies the partition property if and only if it has finite…

Logic · Mathematics 2008-02-03 Thomas Jech , Saharon Shelah

We establish a quantitative version of Oppenheim's conjecture for generic ternary indefinite quadratic forms using an analytic number theory approach. The statements come with power gains and in some cases are essentially optimal

Number Theory · Mathematics 2016-06-15 Jean Bourgain

In this paper, we generalize the finiteness of models theorem in [BCHM06] to Kawamata log terminal pairs with fixed Kodaira dimension. As a consequence, we prove that a Kawamata log terminal pair with $\mathbb{R}-$boundary has a canonical…

Algebraic Geometry · Mathematics 2020-05-08 Junpeng Jiao

We show exactness of the homotopy sequence for the logarithmic fundamental group in the case of log smooth, finitely presented, proper and saturated morphisms of fs log schemes over a field. This generalizes earlier results of Hoshi in the…

Algebraic Geometry · Mathematics 2026-03-23 Mattia Talpo

Let X be a normal projective variety, and let A be an ample Cartier divisor on X. We prove that the twisted cotangent sheaf $\Omega_X \otimes A$ is generically nef with respect to the polarisation A unless X is a projective space. As an…

Algebraic Geometry · Mathematics 2017-10-26 Andreas Höring

Higher-order quantum theory is an extension of quantum theory where one introduces transformations whose input and output are transformations, thus generalizing the notion of channels and quantum operations. The generalization then goes…

Quantum Physics · Physics 2019-05-28 Alessandro Bisio , Paolo Perinotti

We consider a generalized Riemann-Hurwitz formula as it may be applied to rational maps between projective varieties having an indeterminacy set and fold-like singularities. The case of a holomorphic branched covering map is recalled. Then…

Algebraic Topology · Mathematics 2016-02-10 James F. Glazebrook , Alberto Verjovsky

It is proved that, if $K$ is a complete discrete valuation field of mixed characteristic $(0,p)$ with residue field satisfying a mild condition, then any abelian variety over $K$ with potentially good reduction has finite…

Number Theory · Mathematics 2013-04-17 Yusuke Kubo , Yuichiro Taguchi

Using the spectral properties of orthogonal polynomials, we introduce a finite version of quantum field theory for elementary particles. Closed-loop integrals in the Feynman diagrams for computing transition amplitudes are finite.…

General Physics · Physics 2025-10-07 A. D. Alhaidari