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Related papers: Exactness, integrality, and log modifications

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This paper is a revision of the author's old preprint "Exactness, integrality, and log modifications". We will prove that any quasi-compact morphism of fs log schemes can be modified locally on the base to an integral morphism by base…

Algebraic Geometry · Mathematics 2021-01-25 Fumiharu Kato

Many concepts in logarithmic geometry are invariant under log blowups. To formalize this invariance, we introduce the m-open, m-\'etale, m-smooth, m-fppf, and m-fpqc topologies for fs log schemes. These refine the standard topologies from…

Algebraic Geometry · Mathematics 2025-10-29 Xianyu Hu , Maximilian Schimpf

This text is an introduction to the applications of rounding of complex log spaces (also known as Kato-Nakayama or Betti realization) to singularity theory. Log spaces in the sense of Fontaine and Illusie were first described in print by…

Algebraic Geometry · Mathematics 2025-07-17 Patrick Popescu-Pampu

In the category of log schemes, it is unclear how to define the blow-ups for non-strict closed immersions. In this article, we introduce the notion of divided log spaces. We obtain the category of divided log spaces by locally inverting log…

Algebraic Geometry · Mathematics 2024-10-02 Doosung Park

This paper gives a foundation of log smooth deformation theory. We study the infinitesimal liftings of log smooth morphisms and show that the log smooth deformation functor has a representable hull. This deformation theory gives, for…

alg-geom · Mathematics 2008-02-03 Fumiharu Kato

For proper morphisms, we give a functorial flatification algorithm by blow-ups in the spirit of Hironaka's flatification algorithm. In characteristic zero, this gives functorial flatification by blow-ups in smooth centers. We also give a…

Algebraic Geometry · Mathematics 2025-01-16 David Rydh

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

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

Let A be a finite or countable alphabet and let $\theta$ be a literal (anti-)automorphism onto A * (by definition, such a correspondence is determinated by a permutation of the alphabet). This paper deals with sets which are invariant under…

Discrete Mathematics · Computer Science 2018-09-06 Jean Néraud , Carla Selmi

We first introduce and study the notion of multi-weighted blow-ups, which is later used to systematically construct an explicit yet efficient algorithm for functorial logarithmic resolution in characteristic zero, in the sense of Hironaka.…

Algebraic Geometry · Mathematics 2026-05-27 Dan Abramovich , Ming Hao Quek

We continue our study on infinitesimal lifting properties of maps between locally noetherian formal schemes started in math.AG/0604241. In this paper, we focus on some properties which arise specifically in the formal context. In this vein,…

Algebraic Geometry · Mathematics 2008-04-22 Leovigildo Alonso , Ana Jeremias , Marta Perez

Let $f : X \longrightarrow Y$ be a proper and local complete intersection morphism of schemes. We prove that $\mathbb{R}f_{*}$ preserves perfect complexes, without any projectivity or noetherian assumptions. This provides a different proof…

Algebraic Geometry · Mathematics 2012-10-16 B. Toën

A map of fine log schemes $X \to Y$ induces a map from the scheme underlying $X$ to Olsson's algebraic stack of strict morphisms of fine log schemes over $Y$. A sheaf on $X$ is called \emph{log flat over} $Y$ iff it is flat over this…

Algebraic Geometry · Mathematics 2016-01-12 W. D. Gillam

We generalize the Cartier transform of Ogus and Vologodsky to log smooth schemes. More precisely, we generalize a local version of this transform, due to Shiho, and a topos-theoretic version, due to Oyama. Let $k$ be a perfect field of…

Algebraic Geometry · Mathematics 2025-12-15 Sami Fersi

We introduce and study a log discrepancy function on the space of semivaluations centered on an integral noetherian scheme of positive characteristic. Our definition shares many properties with the analogue in characteristic zero; we prove…

Algebraic Geometry · Mathematics 2021-02-16 Eric Canton

In this article, we analyze the connection between the Log De Rham Cohomology of an fs (not necessary log smooth) log scheme $Y$ over $\mathbb C$ (for $Y$ admitting an exact closed immersion into an fs log smooth log scheme over $\mathbb…

Algebraic Geometry · Mathematics 2007-05-23 Bruno Chiarellotto , Marianna Fornasiero

Let $A$ be a finite or countable alphabet and let $\theta$ be literal (anti)morphism onto $A^*$ (by definition, such a correspondence is determinated by a permutation of the alphabet). This paper deals with sets which are invariant under…

Discrete Mathematics · Computer Science 2017-07-28 Jean Néraud , Carla Selmi

In this article, we generalize a previously defined set of axioms for a closure operation that induces balanced big Cohen-Macaulay modules. While the original axioms were only defined in terms of finitely generated modules, these new ones…

Commutative Algebra · Mathematics 2018-02-01 Geoffrey D. Dietz

Let f : X -> Y be a morphism between normal complex varieties, and assume that Y is Kawamata log terminal. Given any differential form, defined on the smooth locus of Y, we construct a "pull-back form" on X. The pull-back map obtained by…

Algebraic Geometry · Mathematics 2013-07-23 Stefan Kebekus

Let $f \colon X \to Y$ be a morphism of concentrated schemes. We characterize $f$-perfect complexes $\mathcal{E}$ as those such that the functor $\mathcal{E} \otimes^{\mathbf{L}}_X \mathbf{L} f^*-$ preserves bounded complexes. We prove, as…

Algebraic Geometry · Mathematics 2023-09-15 Leovigildo Alonso , Ana Jeremias , Fernando Sancho
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