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Related papers: Bounding ramification with coherent sheaves

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This paper introduces an abelian category of logarithmic coherent sheaves that arranges coherent sheaves across all expansions and root stacks of a simple normal crossing degeneration. Formally, logarithmic coherent sheaves are coherent…

Algebraic Geometry · Mathematics 2026-04-08 Hannah Dell , Xianyu Hu , Patrick Kennedy-Hunt , Kabeer Manali Rahul , Maximilian Schimpf

We show that compatible systems of $\ell$-adic sheaves on a scheme of finite type over the ring of integers of a local field are compatible along the boundary up to stratification. This extends a theorem of Deligne on curves over a finite…

Algebraic Geometry · Mathematics 2019-11-13 Qing Lu , Weizhe Zheng

We study the compatibility with proper push-forward of the characteristic cycles of a constructible complex on a smooth variety over a perfect field.

Algebraic Geometry · Mathematics 2020-03-24 Takeshi Saito

Fix a scheme $X$ over a field of characteristic zero that is equipped with an action of a reductive algebraic group $G$. We give necessary and sufficient conditions for a $G$-equivariant coherent sheaf on $X$ or a bounded-above complex of…

Algebraic Geometry · Mathematics 2008-04-21 Thomas Nevins

Over a connected geometrically unibranch scheme $X$ of finite type over a finite field, we show finiteness of the number of irreducible $\bar \Q_\ell$-lisse sheaves, with bounded rank and bounded ramification in the sense of Drinfeld, up to…

Algebraic Geometry · Mathematics 2016-06-21 Hélène Esnault

We present a uniform theory of constructible sheaves on arbitrary schemes with coefficients in topological or even condensed rings. This is accomplished by defining lisse sheaves to be the dualizable objects in the derived infinity-category…

Algebraic Geometry · Mathematics 2023-05-30 Tamir Hemo , Timo Richarz , Jakob Scholbach

We introduce and study configuration schemes, which are obtained by ``glueing'' usual schemes along closed embeddings. The category of coherent sheaves on a configuration scheme is investigated. Smooth configuration schemes provide…

Algebraic Geometry · Mathematics 2007-05-23 Valery A. Lunts

This is a large audience version of our previous work (see math.AG/0301146) in which we prove the existence of an (exact) equivalence between the category of coherent analytic sheaves and the category of $\bar{\partial}$-coherent sheaves.…

Algebraic Geometry · Mathematics 2009-09-29 Nefon Pali

(Makes a Gamma-acylic coherent resolution of a coherent sheaf on a projection scheme.)

alg-geom · Mathematics 2008-02-03 George R. Kempf

In this article, we prove that the Swan conductor of an \'etale sheaf on a smooth variety defined by Abbes and Saito's logarithmic ramification theory can be computed by its classical Swan conductors after restricting it to curves. It…

Algebraic Geometry · Mathematics 2017-04-18 Haoyu Hu

Let $X$ be any rational surface. We construct a tilting bundle $T$ on $X$. Moreover, we can choose $T$ in such way that its endomorphism algebra is quasi-hereditary. In particular, the bounded derived category of coherent sheaves on $X$ is…

Algebraic Geometry · Mathematics 2017-06-27 Lutz Hille , Markus Perling

Let $K$ be a complete discrete valuation field whose residue field is perfect and of positive characteristic, let $X$ be a connected, proper scheme over $\mathcal{O}_K$, and let $U$ be the complement in $X$ of a divisor with simple normal…

Number Theory · Mathematics 2017-03-03 Isabel Leal

Under mild hypotheses, given a scheme $U$ and an open subset $V$ whose complement has codimension at least two, the pushforward of a torsion-free coherent sheaf on $V$ is coherent on $U$. We prove an analog of this result in the context of…

Algebraic Geometry · Mathematics 2025-04-08 David Harbater , Julia Hartmann , Daniel Krashen

We establish a criterion for sheaves on an adically complete DG scheme to be coherent. We deduce a description of coherent sheaves on an adically complete lci singularity in terms of modules for a DG Lie algebra.

Algebraic Geometry · Mathematics 2012-02-24 Sam Raskin

We investigate sheaves supported on the zero section of the total space of a locally-free sheaf E on a smooth, projective variety X when the top exterior power of E is isomorphic to the canonical bundle of X. We rephrase this construction…

Algebraic Geometry · Mathematics 2008-01-24 Matthew Robert Ballard

For a constructible \'etale sheaf on a smooth variety of positive characteristic ramified along an effective divisor, the largest slope in Abbes and Saito's ramification theory of the sheaf gives a divisor with rational coefficients called…

Algebraic Geometry · Mathematics 2022-04-27 Haoyu Hu

Given a normal projective irreducible stack $\mathscr X$ over an algebraically closed field of characteristic zero we consider framed sheaves on $\mathscr X$, i.e., pairs $(\mathcal E,\phi_{\mathcal E})$, where $\mathcal E$ is a coherent…

Algebraic Geometry · Mathematics 2015-02-27 Ugo Bruzzo , Francesco Sala

Let $X_N$ be the second infinitesimal neighborhood of a closed point in $N$-dimensional affine space. In this note we study $D^b(coh\, X_N)$, the bounded derived category of coherent sheaves on $X_N$. We show that for $N\geq 2$ the lattice…

Algebraic Geometry · Mathematics 2020-03-25 Alexey Elagin , Valery A. Lunts

In this article, we give a bound for the wild ramification of the monodromy action on the nearby cycles complex of a locally constant \'etale sheaf on the generic fiber of a smooth scheme over an equal characteristic trait in terms of Abbes…

Algebraic Geometry · Mathematics 2022-04-27 Haoyu Hu , Jean-Baptiste Teyssier

We prove uniform boundedness statements for semistable pure sheaves on projective manifolds. For example, we prove that the set of isomorphism classes of pure sheaves of dimension 2 that are slope semistable with respect to ample classes…

Algebraic Geometry · Mathematics 2024-03-20 Mihai Pavel , Julius Ross , Matei Toma
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