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Related papers: A Note on Numerical Perverse Sheaves

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This is the first of two papers studying moduli spaces of a certain class of coherent sheaves, which we call {\it stable perverse coherent sheaves}, on the blowup of a projective surface. They are used to relate usual moduli spaces of…

Algebraic Geometry · Mathematics 2008-06-03 Hiraku Nakajima , Kota Yoshioka

We introduce, on a topological space X, a class of stacks of abelian categories we call "stacks of type P." This class of stacks includes the stack of perverse sheaves (of any perversity, constructible with respect to a fixed…

Representation Theory · Mathematics 2008-01-22 David Treumann

We develop a unified approach for identifying spaces of stability conditions of triangulated categories arising from weighted marked surfaces with moduli spaces of quadratic differentials. This approach is based on the notion of a perverse…

Representation Theory · Mathematics 2024-06-26 Merlin Christ , Fabian Haiden , Yu Qiu

In this paper we prove that the category of parity complexes on the flag variety of a complex connected reductive group is a "graded version" of the category of tilting perverse sheaves on the flag variety of the dual group, for any field…

Representation Theory · Mathematics 2015-02-09 Pramod N. Achar , Simon Riche

We give a geometric construction of tilting perverse sheaves using stratified Morse theory, torus actions, and nearby cycles.

Representation Theory · Mathematics 2007-05-23 David Nadler

We give a formalism of mixed sheaves on varieties over a subfield of the complex number field.

Algebraic Geometry · Mathematics 2007-05-23 Morihiko Saito

We consider a fixed block for the equivariant perverse sheaves with nilpotent support in the $1$-graded ccomponent of a semisimple cyclically graded Lie algebra. We give a combinatorial parametrization of the simple objects in that block.

Representation Theory · Mathematics 2016-10-03 George Lusztig , Zhiwei Yun

In recent work, Graham has constructed a variety with a map to the nilpotent cone which is similar in some ways to the Springer resolution. One aspect in which Graham's map differs is that it is not in general an isomorphism over the…

Representation Theory · Mathematics 2019-12-20 Amber Russell

In characteristic zero, Bezrukavnikov has shown that the category of perverse coherent sheaves on the nilpotent cone of a simply connected semisimple algebraic group is quasi-hereditary, and that it is derived-equivalent to the category of…

Representation Theory · Mathematics 2011-09-14 Pramod N. Achar

We review the theory of non-commutative deformations of sheaves and describe a versal deformation by using an A-infinity algebra and the change of differentials of an injective resolution. We give some explicit non-trivial examples.

Algebraic Geometry · Mathematics 2019-10-29 Yujiro Kawamata

We show that perverse character varieties are (quasi-)affine. We do this in a purely stack-theoretic fashion, by exhibiting enough sections of the structure sheaf.

Algebraic Geometry · Mathematics 2026-05-26 Enrico Lampetti , Michele Pernice

This is a mostly expository paper, intended to explain a very natural relationship between two a priori distinct notions appearing in the literature: Generic Vanishing in the context of vanishing theorems and birational geometry, and…

Algebraic Geometry · Mathematics 2009-11-23 Mihnea Popa

In the first section we study a functor of Bezrukavnikov, Finkelberg and Ostrik defined on character sheaves; we compute it in a Grothendieck group taking weights into account. In the second section we enlarge the class of character sheaves…

Representation Theory · Mathematics 2008-05-07 G. Lusztig

We relate shuffle algebras, as defined by Nichols, Feigin-Odesskii and Rosso, to perverse sheaves on symmetric products of the complex line (i.e., on the spaces of monic polynomials stratified by multiplicities of roots). More precisely, we…

Algebraic Topology · Mathematics 2020-01-14 Mikhail Kapranov , Vadim Schechtman

In this note, we consider perverse sheaves on the nilpotent cone. We prove orthogonality relations for the equivariant category of sheaves on the nilpotent cone in a method similar to Lusztig's for character sheaves. We also consider…

Representation Theory · Mathematics 2016-11-07 Laura Rider , Amber Russell

We give a characterization of the support and cosupport conditions for a perverse sheaf in terms of the Whitney filtration.

Algebraic Geometry · Mathematics 2022-07-07 David B. Massey

We revisit some of the basic results of generic vanishing theory, as pioneered by Green and Lazarsfeld, in the context of constructible sheaves. Using the language of perverse sheaves, we give new proofs of some of the basic results of this…

Algebraic Geometry · Mathematics 2017-02-22 Bhargav Bhatt , Christian Schnell , Peter Scholze

Working over imperfect fields, we give a comprehensive classification of genus-one curves that are regular but not geometrically regular, extending the known case of geometrically reduced curves. The description is given intrinsically, in…

Algebraic Geometry · Mathematics 2022-11-09 Stefan Schröer

We consider a hyperplane arrangement in $\mathbb{C}^n$ defined over $\mathbb{R}$, and the associated natural stratification of $\mathbb{C}^n$. The category of perverse sheaves smooth with respect to this stratification was described by…

Representation Theory · Mathematics 2020-11-17 Asilata Bapat

Perverse schober defined by Kapranov--Schechtman is a categorification of the notion of perverse sheaf. In their definition, a key ingredient is certain purity property of perverse sheaves. In this short note, we attempt to describe a real…

Algebraic Geometry · Mathematics 2019-02-19 Tatsuki Kuwagaki