English
Related papers

Related papers: Perverse sheaves on semiabelian varieties

200 papers

In the strict semi stable reduction situation, we describe the various filtrations of the perverse sheaf of nearby cycles in terms of irreducible perverse sheaves together with the action of the monodromy operator. We then study the…

Algebraic Geometry · Mathematics 2026-01-06 Pascal Boyer

We construct a quasi-coherent sheaf of associative algebras which controls a category of $AV$-modules over a smooth quasi-projective variety. We establish a local structure theorem, proving that in \'etale charts these associative algebras…

Representation Theory · Mathematics 2026-02-02 Yuly Billig , Colin Ingalls

We prove that a category of degree zero vector bundles with "potentially strongly semistable reduction" on a p-adic curve is a neutral Tannakian category. We also make a first study of the corresponding affine group scheme. In particular,…

Algebraic Geometry · Mathematics 2007-05-23 C. Deninger , A. Werner

We study the interaction between Fourier-Mukai transforms and perverse filtrations for a certain class of dualizable abelian fibrations. Multiplicativity of the perverse filtration and the "Perverse $\supset$ Chern" phenomenon for these…

Algebraic Geometry · Mathematics 2025-10-09 Davesh Maulik , Junliang Shen , Qizheng Yin

We prove a theorem relating torus-equivariant coherent sheaves on toric varieties to polyhedrally-constructible sheaves on a vector space. At the level of K-theory, the theorem recovers Morelli's description of the K-theory of a smooth…

Algebraic Geometry · Mathematics 2011-09-23 Bohan Fang , Chiu-Chu Melissa Liu , David Treumann , Eric Zaslow

We study the question when a category of ind-objects is abelian. Our answer allows a further generalization of the notion of weakly Tannakian categories introduced by the author. As an application we show that, under suitable conditions,…

Algebraic Geometry · Mathematics 2019-02-20 Daniel Schäppi

This paper contains a Kawamata-Viehweg-Koll\'ar type vanishing theorem for vector bundles. In order to formulate and prove this cleanly, we introduce a class of sheaves that automatically satisfies a vanishing theorem. This is obtained by…

Algebraic Geometry · Mathematics 2007-05-23 Donu Arapura

Perverse schobers are categorical analogs of perverse sheaves. Examples arise from varieties admitting flops, determined by diagrams of derived categories of coherent sheaves associated to the flop: in this paper we construct mirror…

Algebraic Geometry · Mathematics 2019-03-28 W. Donovan , T. Kuwagaki

We study the categories $\mathrm{Perv}_{\mathrm{thin}}$ and $\mathrm{Perv}_{\mathrm{thick}}$ of Iwahori-equivariant perverse sheaves on the thin and thick affine flag varieties associated to a split reductive group $G$. An earlier work of…

Representation Theory · Mathematics 2026-04-06 Roman Bezrukavnikov , Calder Morton-Ferguson

We prove a conjecture by Lusztig, which describes the tensor categories of perverse sheaves on affine flag manifolds, with tensor structure provided by truncated convolution, in terms of the Langlands dual group. We also give a geometric…

Representation Theory · Mathematics 2012-01-04 Roman Bezrukavnikov

In this first of a series of articles on standard extension algebras we study standard perverse sheaves on varieties with $\mathbb{G}_m$-actions. Based on Braden's hyperbolic localisation, we describe their extension algebra geometrically…

Representation Theory · Mathematics 2023-10-16 Jens Niklas Eberhardt , Catharina Stroppel

To any closed subvariety $Y$ of a complex abelian variety one can attach a reductive algebraic group $G$ which is determined by the decomposition of the convolution powers of $Y$ via a certain Tannakian formalism. For a theta divisor $Y$ on…

Algebraic Geometry · Mathematics 2016-03-22 Thomas Krämer , Rainer Weissauer

We consider essentially small rigid tensor categories (not necessarily abelian) which have a faithful tensor functor to a category of super vector spaces over a field of characteristic 0. It is shown how to construct for each such tensor…

Category Theory · Mathematics 2021-01-01 Peter O'Sullivan

We survey nearby and vanishing cycles for both perverse sheaves and D-modules under analytic setting. Following ideas of A. Beilinson, M. Kashiwara and M. Saito, we explain in detail the proof of the comparison theorem between them in the…

Algebraic Geometry · Mathematics 2020-01-07 Lei Wu

The goal of this paper is to construct a category of motivic "sheaves" on an algebraic variety defined over a subfield of C, using Nori's method. This categoryis abelian and it possesses faithful exact realization functors to the…

Algebraic Geometry · Mathematics 2012-10-11 Donu Arapura

In this paper we construct a tilting sheaf for Severi-Brauer Varieties and Involution Varieties. This sheaf relates the derived category of each variety to the derived category of modules over a ring whose semisimple component consists of…

Algebraic Geometry · Mathematics 2012-04-04 Mark Blunk

We introduce a class of perverse sheaves on a partial flag manifold of a connected reductive group G defined over a finite field which are equivariant under the action of the group of rational points of G. The definition of this class is…

Representation Theory · Mathematics 2007-05-23 G. Lusztig

We give a moduli-theoretic proof of the classical theorem of Gabriel, stating that a scheme can be reconstructed from the abelian category of quasi-coherent sheaves over it. The methods employed are elementary and allow us to extend the…

Algebraic Geometry · Mathematics 2013-10-25 John Calabrese , Michael Groechenig

Inspired by symplectic geometry and a microlocal characterizations of perverse (constructible) sheaves we consider an alternative definition of perverse coherent sheaves. We show that a coherent sheaf is perverse if and only if…

Algebraic Geometry · Mathematics 2015-09-30 Clemens Koppensteiner

Achar has recently introduced a family of t-structures on the derived category of equivariant coherent sheaves on a $G$-scheme, generalizing the perverse coherent t-structures of Bezrukavnikov and Deligne. They are called \emph{staggered}…

Algebraic Geometry · Mathematics 2008-06-05 David Treumann