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For a smooth projective complex variety whose Albanese morphism is finite, we show that every Bridgeland stability condition on its bounded derived category of coherent sheaves is geometric, in the sense that all skyscraper sheaves are…

Algebraic Geometry · Mathematics 2022-01-24 Lie Fu , Chunyi Li , Xiaolei Zhao

Let $f$ be a non-invertible irreducible Anosov map on $d$-torus. We show that if the stable bundle of $f$ is one-dimensional, then $f$ has the integrable unstable bundle, if and only if, every periodic point of $f$ admits the same Lyapunov…

Dynamical Systems · Mathematics 2023-07-05 Jinpeng An , Shaobo Gan , Ruihao Gu , Yi Shi

The purpose of this paper is to provide a very short proof of a generalized categorified version, within the motivic stable homotopy category of Morel and Voevodsky, of the integral identity for virtual motives conjectured by Kontsevich and…

Algebraic Geometry · Mathematics 2024-10-16 Florian Ivorra

The goal of this paper is to motivate a boundedness conjecture on nearby slopes of $\ell$-adic sheaves in positive characteristic, and to prove it for smooth curves. For a constructible $\ell$-adic sheaf, we prove the finiteness of the set…

Algebraic Geometry · Mathematics 2015-06-10 Jean-Baptiste Teyssier

Let S be an essentially smooth scheme over a field and l a prime number invertible on S. We show that the algebra of bistable operations in the mod l motivic cohomology of smooth S-schemes is generated by the motivic Steenrod operations.…

Algebraic Geometry · Mathematics 2013-08-01 Marc Hoyois , Shane Kelly , Paul Arne Østvær

It is proved that for any cohomology theory A in the sense of [PS] and any essentially k-smooth semi-local X the Cousin complex is exact. As a consequence we prove that for any integer n the Nisnevich sheaf A^n_Nis, associated with the…

Algebraic Geometry · Mathematics 2017-07-07 Ivan Panin

We prove a version of the Gindikin-Karpelevich formula for untwisted affine Kac-Moody groups over a local field of positive characteristic. The proof is geometric and it is based on the results of [1] about intersection cohomology of…

Representation Theory · Mathematics 2011-12-15 Alexander Braverman , Michael Finkelberg , David Kazhdan

For a reductive group $G$, we prove that complex irreducible rigid $G$-local systems with quasi-unipotent monodromies and finite order abelianization on a smooth curve are motivic, generalizing a theorem of Katz for $GL_n$. We do so by…

Algebraic Geometry · Mathematics 2024-07-30 Joakim Færgeman

The algebraic stability theorem for $\mathbb{R}$-persistence modules is a fundamental result in topological data analysis. We present a stability theorem for $n$-dimensional rectangle decomposable persistence modules up to a constant…

Algebraic Topology · Mathematics 2020-01-22 Håvard Bakke Bjerkevik

We show that any extremal contraction from a smooth projective variety with dimension less than or equal to three appears as a moduli space of (semi)stable objects in the derived category of coherent sheaves.

Algebraic Geometry · Mathematics 2012-04-04 Yukinobu Toda

For any smooth projective variety $X$ of dimension $n$ over an algebraically closed field $k$ of characteristic $p>0$ with $\mu(\Omega^1_X)>0$. If ${\rm T}^{\ell}(\Omega^1_X)$ ($0<\ell<n(p-1)$) are semi-stable, then the sheaf $B^1_X$ of…

Algebraic Geometry · Mathematics 2009-05-14 Xiaotao Sun

Let $X$ be a smooth scheme over a finite field of characteristic $p$. Consider the coefficient objects of locally constant rank on $X$ in $\ell$-adic Weil cohomology: these are lisse Weil sheaves in \'etale cohomology when $\ell \neq p$,…

Number Theory · Mathematics 2025-12-17 Kiran S. Kedlaya

In this paper we prove motivic versions of the Langlands-Shelstad Fundamental Lemma and Ng\^o's Geometric Stabilization. To achieve this, we follow the strategy from the recent proof by Groechenig, Wyss and Ziegler which avoided the use of…

Algebraic Geometry · Mathematics 2026-02-12 Arthur Forey , François Loeser , Dimitri Wyss

We introduce n-generated sheaves and n-motivic sheaves, describing completely for n = 0, 1 and proposing a conjecture for n > 1. We then obtain functors L\pi_0 and LAlb on DM_{eff}(k) deriving \pi_0 and Alb. The functor LAlb extends the one…

Algebraic Geometry · Mathematics 2009-09-07 J. Ayoub , L. Barbieri-Viale

A sheaf of modules on a site is said to be internally projective if sheaf hom with the module preserves epimorphism. In this note, we give an example showing that internally projective sheaves of abelian groups are not in general stable…

Category Theory · Mathematics 2024-09-20 David Wärn

We consider the category of Deligne 1-motives over a perfect field k of exponential characteristic p and its derived category for a suitable exact structure after inverting p. As a first result, we provide a fully faithful embedding into an…

Algebraic Geometry · Mathematics 2009-09-29 Luca Barbieri-Viale , Bruno Kahn

Relying on the techniques and ideas from our recent paper [13], we prove several anti-classification results for various rigidity conditions in countable abelian and nilpotent groups. We prove three main theorems: (1) the rigid abelian…

Logic · Mathematics 2023-12-06 Gianluca Paolini , Saharon Shelah

We lift the classical theorem of Arnol'd on homological stability for configurations spaces of the plane to the motivic world. More precisely, we prove that the schemes of unordered configurations of points in the affine line satisfy…

Algebraic Topology · Mathematics 2016-10-12 Geoffroy Horel

We extend the methods of geometric invariant theory to actions of non--reductive groups in the case of homomorphisms between decomposable sheaves whose automorphism groups are non--reductive. Given a linearization of the natural action of…

Algebraic Geometry · Mathematics 2007-05-23 J. M. Drezet , G. Trautmann

In this note we will illustrate a method for computing the $\pi_0$ of the effective log motive of a smooth and proper variety over a perfect field $k$ and show that it is $\mathbf{A}^1$-invariant. We will apply this to compute the first…

Algebraic Geometry · Mathematics 2026-03-12 Alberto Merici