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Related papers: Perverse Sheaves on Real Loop Grassmannians

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We discuss what is known about the structure of the bounded derived categories of coherent sheaves on Grassmannians of simple algebraic groups.

Algebraic Geometry · Mathematics 2025-06-13 Anton Fonarev

We study the category of G(O)-equivariant perverse coherent sheaves on the affine Grassmannian of G. This coherent Satake category is not semisimple and its convolution product is not symmetric, in contrast with the usual constructible…

Representation Theory · Mathematics 2018-04-30 Sabin Cautis , Harold Williams

For a fixed parabolic subalgebra p of gl(n,C) we prove that the centre of the principal block O(p) of the parabolic category O is naturally isomorphic to the cohomology ring of the corresponding Springer fibre. We give a diagrammatic…

Representation Theory · Mathematics 2014-01-14 Catharina Stroppel

Let X be an algebraic variety with an action of an algebraic group G. Suppose X has a full exceptional collection of sheaves, and these sheaves are invariant under the action of the group. We construct a semiorthogonal decomposition of…

Algebraic Geometry · Mathematics 2015-05-13 Alexei Elagin

For each integer $k\geq 4$ we describe diagrammatically a positively graded Koszul algebra $\mathbb{D}_k$ such that the category of finite dimensional $\mathbb{D}_k$-modules is equivalent to the category of perverse sheaves on the isotropic…

Representation Theory · Mathematics 2016-08-02 Michael Ehrig , Catharina Stroppel

We propose the notion of perverse coherent sheaves for symplectic singularities and study its properties. In particular, it gives a basis of simple objects in the Grothendieck group of Poisson sheaves. We show that perverse coherent bases…

Representation Theory · Mathematics 2025-10-28 Ilya Dumanski

When $W$ is a finite Coxeter group acting by its reflection representation on $E$, we describe the category ${\mathsf{Perv}}_W(E_{\mathbb C}, {\mathcal{H}}_{\mathbb C})$ of $W$-equivariant perverse sheaves on $E_{\mathbb C}$, smooth with…

Representation Theory · Mathematics 2023-06-22 Martin H. Weissman

This paper is the first in a series. The main goal of the series is to present a geometric construction of certain remarkable tensor categories arising from quantum groups coresponding to the value of deformation parameter $q$ equal to a…

High Energy Physics - Theory · Physics 2008-02-03 M. Finkelberg , V. Schechtman

Using techniques of [BKV], we construct a perverse t-structure on the infinity-category of l-adic LG-equivariant sheaves on the regular-semisimple bounded locus of the loop group LG and prove that the derived $\tau$-coinvariants of affine…

Algebraic Geometry · Mathematics 2025-06-25 Alexis Bouthier , David Kazhdan , Yakov Varshavsky

In this paper we study the derived categories of coherent sheaves on Grassmannians $\operatorname{Gr}(k,n),$ defined over the ring of integers. We prove that the category $D^b(\operatorname{Gr}(k,n))$ has a semi-orthogonal decomposition,…

Algebraic Geometry · Mathematics 2025-02-10 Alexander I. Efimov

In their article "Elementary construction of perverse sheaves", R.MacPherson and K. Vilonen show that on a Thom-Mather space X the category PervX of perverse sheaves is equivalent to the category C(F, G, T) whose objects are data of…

Algebraic Geometry · Mathematics 2011-03-23 Delphine Dupont

We give a Tannakian description for categories of l-adic perverse sheaves on semiabelian varieties which combines a construction of Gabber and Loeser for algebraic tori with a generic vanishing theorem for the cohomology of constructible…

Algebraic Geometry · Mathematics 2015-03-30 Thomas Krämer

It is usually not straightforward to work with the category of perverse sheaves on a variety using only its definition as a heart of a $t$-structure. In this paper, the category of perverse sheaves on a smooth toric variety with its orbit…

Algebraic Geometry · Mathematics 2024-12-30 Sergey Guminov

We consider the category of perverse sheaves on a complex vector space smooth with respect to a stratification given by an arrangement of hyperplanes with real equations. As shown in an earlier wotk of two of the authors, this category can…

Algebraic Topology · Mathematics 2022-06-28 Michael Finkelberg , Mikhail Kapranov , Vadim Schechtman

Let $k$ be an algebraically closed field of characteristic $p$. Denote by $W(k)$ the ring of Witt vectors of $k$. Let $F$ denote a totally ramified finite extension of $W(k)[1/p]$ and $\mathcal{O}$ the its ring of integers. For a connected…

Algebraic Geometry · Mathematics 2019-03-28 Jize Yu

We define a quantum analogue of the Grothendieck ring of finite dimensional modules of a quantum affine algebra of simply laced type. The construction is based on perverse sheaves on a variety related to quivers. We get also a new geometric…

Quantum Algebra · Mathematics 2007-05-23 Michela Varagnolo , Eric Vasserot

A class of perverse sheaves on framed representation varieties of the Jordan quiver is defined. Its relationship with product of symmetric groups, tensor product of Schur algebras, and tensor product of Fock spaces are addressed.

Representation Theory · Mathematics 2012-09-18 Yiqiang Li

We describe diagrammatically a positively graded Koszul algebra \mathbb{D}_k such that the category of finite dimensional \mathbb{D}_k-modules is equivalent to the category of perverse sheaves on the isotropic Grassmannian of type D_k…

Representation Theory · Mathematics 2013-06-19 Michael Ehrig , Catharina Stroppel

The goal of this paper is to explain how basic properties of perverse sheaves sometimes translate via Riemann-Hilbert correspondences (in both characteristic $0$ and characteristic $p$) to highly non-trivial properties of singularities,…

Algebraic Geometry · Mathematics 2025-03-26 Bhargav Bhatt , Manuel Blickle , Gennady Lyubeznik , Anurag K. Singh , Wenliang Zhang

The convolution ring $K^{GL_n(\mathcal{O})\rtimes\mathbb{C}^\times}(\mathrm{Gr}_{GL_n})$ was identified with a quantum unipotent cell of the loop group $LSL_2$ in [Cautis-Williams, J. Amer. Math. Soc. 32 (2019), pp. 709-778]. We identify…

Representation Theory · Mathematics 2024-06-11 Michael Finkelberg , Ryo Fujita