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Related papers: Degenerate Perverse Sheaves on Abelian Varieties

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Let X be a scheme of finite type over a Noetherian base scheme S admitting a dualizing complex, and let U be an open subset whose complement has codimension at least 2. We extend the Deligne-Bezrukavnikov theory of perverse coherent sheaves…

Representation Theory · Mathematics 2017-01-03 Pramod N. Achar , Daniel S. Sage

Let $k$ be a field of characteristic $0$, let $S$ be a smooth, geometrically connected variety over $k$, with generic point $\eta$, and $f:\mathbb{X}\rightarrow S$ a morphism separated and of finite type. Fix a prime $\ell$. Let…

Algebraic Geometry · Mathematics 2025-07-31 Anna Cadoret , Haohao Liu

We show that there is a natural perverse sheaf on the moduli space of semistable sheaves on a smooth projective Calabi-Yau 3-fold which is locally the perverse sheaf of vanishing cycles for a local Chern-Simons functional. This gives us a…

Algebraic Geometry · Mathematics 2012-10-18 Young-Hoon Kiem , Jun Li

We introduce and study the category of modular (i.e. with coefficient of positive characteristic) monodromic perverse sheaves on complex stratified $T$-varieties, with $T$ a complex algebraic torus. In particular, we show that under…

Representation Theory · Mathematics 2020-05-07 Valentin Gouttard

The goal of this work is to construct a perverse t-structure on the infinity-category of l-adic LG-equivariant sheaves on the loop Lie algebra Lg and to show that the affine Grothendieck-Springer sheaf S is perverse. Moreover, S is an…

Algebraic Geometry · Mathematics 2022-09-21 Alexis Bouthier , David Kazhdan , Yakov Varshavsky

Another introduction to perverse sheaves with some exercises. Expanded version of five lectures at the 2015 PCMI.

Algebraic Geometry · Mathematics 2016-11-15 Mark Andrea A. de Cataldo

We study a certain class of simple abelian varieties of type $\mathrm{IV}$ (in Albert's classification) over number fields with Mumford-Tate groups of type $A$. In particular, we show that such abelian varieties have ordinary reduction away…

Number Theory · Mathematics 2018-08-17 Steve Thakur

Perverse schobers are conjectural categorical analogs of perverse sheaves. We show that such structures appear naturally in Homological Minimal Model Program which studies the effect of birational transformations such as flops, on the…

Algebraic Geometry · Mathematics 2018-01-26 Alexey Bondal , Mikhail Kapranov , Vadim Schechtman

We study extension of scalars for sheaves of vector spaces, assembling results that follow from well-known statements about vector spaces, but also developing some complements. In particular, we formulate Galois descent in this context, and…

Algebraic Geometry · Mathematics 2025-10-22 Andreas Hohl

The characteristic cycle of a complex of sheaves on a complex analytic space provides weak information about the complex; essentially, it yields the Euler characteristics of the hypercohomology of normal data to strata. We show how perverse…

Algebraic Geometry · Mathematics 2007-05-23 David B. Massey

We describe the set of characteristic polynomials of abelian varieties of dimension 4 over finite fields.

Algebraic Geometry · Mathematics 2011-01-27 Safia Haloui , Vijaykumar Singh

We describe the set of characteristic polynomials of abelian varieties of dimension 3 over finite fields.

Algebraic Geometry · Mathematics 2010-07-28 Safia Haloui

Perverse schobers are categorifications of perverse sheaves. We construct a perverse schober on a partial compactification of the stringy K\"ahler moduli space (SKMS) associated by Halpern-Leistner and Sam to a quasi-symmetric…

Algebraic Geometry · Mathematics 2019-09-06 Špela Špenko , Michel Van den Bergh

We present a result which can be used for stratifications with conical singularities to deduce that a perverse sheaf (in particular, an intersection homology sheaf) has reducible characteristic variety, given a hypothesis on the monodromy…

Algebraic Geometry · Mathematics 2007-05-23 Tom Braden

If $X$ is an abelian variety over a field and $L$ is an invertible sheaf, we know that the degree of the 0-cycle $L^g$ is divisible by $g!$. As a 0-cycle, it is not, even over a field of cohomological dimension 1. But we show that over a…

Algebraic Geometry · Mathematics 2007-05-23 Hélène Esnault

Given a perverse sheaf on the moduli stack of principally polarized abelian varieties or the moduli stack of smooth curves with n marked points over a field of characteristic zero, we prove that the (orbifold) Euler characteristic is…

Algebraic Geometry · Mathematics 2025-12-08 Donu Arapura , Deepam Patel

We show that any abelian variety that is not affine has a nontrivial strongly abelian subvariety. In later papers in this sequence we apply this result to the study of minimal abelian varieties.

Logic · Mathematics 2020-08-21 Keith A. Kearnes , Emil W. Kiss , Agnes Szendrei

We prove an analog of the Gauss-Bonnet formula for constructible sheaves on reductive groups. As a corollary from this formula we get that if a perverse sheaf on a reductive group is equivariant under the adjoint action, then its Euler…

Algebraic Geometry · Mathematics 2007-05-23 Valentina Kiritchenko

We provide a description of Iwahori-Whittaker equivariant perverse sheaves on affine flag varieties associated to tamely ramified reductive groups, in terms of Langlands dual data. This extends the work of Arkhipov-Bezrukavnikov from the…

Representation Theory · Mathematics 2024-11-06 Rızacan Çiloğlu

In this paper we consider ideal sheaves associated to the singular loci of a divisor in a linear system $|L|$ of an ample line bundle on a complex abelian variety. We prove an effective result on their (continuous) global generation, after…

Algebraic Geometry · Mathematics 2008-03-28 Luigi Lombardi , Francesco Malaspina