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Related papers: Logarithmic Flatness

200 papers

We discuss log flat topology and log flat descents of log schemes

Algebraic Geometry · Mathematics 2019-10-01 Kazuya Kato

We develop the foundations of logarithmic structures beyond the standard finiteness conditions. The motivation is the study of semistable models over general valuation rings. The key new notion is that of a morphism of finite presentation…

Algebraic Geometry · Mathematics 2024-11-22 Piotr Achinger , Katharina Hübner , Marcin Lara , Jakob Stix

We use orbifold structures to deduce degeneracy statements for holomorphic maps into logarithmic surfaces. We improve former results in the smooth case and generalize them to singular pairs. In particular, we give applications on nodal…

Algebraic Geometry · Mathematics 2009-03-18 Erwan Rousseau

Let $\mathcal{X}$ be a smooth Artin stack with properly stable good moduli space $\pi\colon\mathcal{X} \to X$. The purpose of this paper is to prove that a simple geometric criterion can often characterize when the moduli space $X$ is…

Representation Theory · Mathematics 2024-02-16 Dan Edidin , Matthew Satriano , Spencer Whitehead

The critical loci of a map $f:X\to Y$ between smooth schemes over a field $k$ are the locally closed subschemes $\Sigma^i(f)\subseteq X$ where the differential of $f$ has constant rank. We prove that if $f : X\to \mathbb A^r$ is the general…

Algebraic Geometry · Mathematics 2020-06-12 Lucas Braune

We give cohomological criteria for logarithmic good reduction of elliptic surfaces up to modification. Along the way, we prove several more general results about such surfaces in positive characteristic, as well as about log smooth…

Algebraic Geometry · Mathematics 2022-12-05 Otto Overkamp , Arne Smeets

To a homology theory one can associate an additive site and a new homological functor with values in the category of additive sheaves on that site. If this category of sheaves can be shown to be equivalent to a category of comodules of a…

Algebraic Topology · Mathematics 2020-11-25 Daniel Schäppi

We show that there is a logarithmic algebraic space parameterizing logarithmic morphisms between fixed logarithmic schemes when those logarithmic schemes satisfy natural hypotheses. As a corollary, we obtain the algebraicity of the stack of…

Algebraic Geometry · Mathematics 2016-07-13 Jonathan Wise

It is classically known that complete flat surfaces in Euclidean 3-space are cylinders over space curves. This implies that the study of global behaviour of flat surfaces requires the study of singular points as well. If a flat surface $f$…

Differential Geometry · Mathematics 2008-12-25 Satoko Murata , Masaaki Umehara

We establish normal form theorems for a large class of singular flat connections on complex manifolds, including connections with logarithmic poles along weighted homogeneous Saito free divisors. As a result, we show that the moduli spaces…

Algebraic Geometry · Mathematics 2022-09-02 Francis Bischoff

Let $X\to Y^0$ be an abelian prime-to-$p$ Galois covering of smooth schemes over a perfect field $k$ of characteristic $p>0$. Let $Y$ be a smooth compactification of $Y^0$ such that $Y-Y^0$ is a normal crossings divisor on $Y$. We describe…

Representation Theory · Mathematics 2014-08-15 Elmar Grosse-Klönne

In this article, we study projective log smooth pairs with numerically flat normalized logarithmic tangent bundle. Generalizing works of Jahnke-Radloff and Greb-Kebekus-Peternell, we show that, passing to an appropriate finite cover and up…

Algebraic Geometry · Mathematics 2021-12-13 Stéphane Druel

Raynaud--Gruson characterized flat and pure morphisms between affine schemes in terms of projective modules. We give a similar characterization for non-affine morphisms. As an application, we show that every quasi-coherent sheaf is the…

Algebraic Geometry · Mathematics 2016-09-01 David Rydh

The logarithmic multiplicative group is a proper group object in logarithmic schemes, which morally compactifies the usual multiplicative group. We study the structure of the stacks of logarithmic maps from rational curves to this…

Algebraic Geometry · Mathematics 2020-03-31 Dhruv Ranganathan , Jonathan Wise

I extend the definitions of schemes relative to monoids with zero - and therefore, toric geometry - to the world of formal schemes. This expands the usual framework to include, for instance, models for Mumford's degenerating Abelian…

Algebraic Geometry · Mathematics 2015-05-29 Andrew W. Macpherson

In the study of holomorphic maps, the term "rigidity" refers to certain types of results that give us very specific information about a general class of holomorphic maps owing to the geometry of their domains or target spaces. Under this…

Complex Variables · Mathematics 2015-08-28 Gautam Bharali , Indranil Biswas

Recently, many authors have embraced the study of certain properties of modules such as projectivity, injectivity and flatness from an alternative point of view. This way, Durgun has introduced absolutely pure domains of modules as a mean…

Algebraic Geometry · Mathematics 2024-11-15 Soumia Mamdouhi

We introduce the notion of a regular integrable connection on a smooth log scheme over $\mathbf{C}$ and construct an equivalence between the category of such connections and the category of integrable connections on its analytification,…

Algebraic Geometry · Mathematics 2023-04-04 Piotr Achinger

We define the notion of generalized logarithmic sheaves on a smooth projective surface, associated to a pair consisting of a reduced curve and some fixed points on it. We then set up the study of the Torelli property in this setting,…

Algebraic Geometry · Mathematics 2023-02-16 Sukmoon Huh , Simone Marchesi , Joan Pons-Llopis , Jean Vallès

To a smooth and proper morphism $\mathcal{X}\to U$ with quasicompact semiseparated target we associate a sheaf in the \'etale topology, which takes an affine $U$-scheme $V$ to the set of $V$-linear semiorthogonal decompositions (of fixed…

Algebraic Geometry · Mathematics 2025-11-17 Pieter Belmans , Shinnosuke Okawa , Andrea T. Ricolfi