English
Related papers

Related papers: Equivariant Sheaves on Flag Varieties

200 papers

In this paper we extend Beilinson's realization formalism for triangulated categories and filtered triangulated categories to a pseudofunctorial and pseudonatural setting. As a consequence we prove an equivariant version of Beilinson's…

Algebraic Geometry · Mathematics 2024-01-19 Geoff Vooys

Given a bundle gerbe on a compact smooth manifold or, more generally, on a compact \'etale Lie groupoid $M$, we show that the corresponding category of gerbe modules, if it is non-trivial, is equivalent to the category of finitely generated…

Algebraic Topology · Mathematics 2014-01-14 Christoph Schweigert , Christopher Tropp , Alessandro Valentino

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

Let $X$ be an affine, smooth, and Noetherian scheme over $\mathbb{C}$ acted on by an affine algebraic group $G$. Applying the technique developed in Arkhipov and {\O}rsted (2018a, 2018b), we define a dg-model for the derived category of…

Representation Theory · Mathematics 2023-02-03 Sergey Arkhipov , Sebastian Ørsted

Given the nilpotent cone of a complex reductive Lie algebra, we consider its equivariant constructible derived category of sheaves with coefficients in an arbitrary field. This category and its subcategory of perverse sheaves play an…

Representation Theory · Mathematics 2012-07-31 Pramod N. Achar , Carl Mautner

Let $X$ be a finite connected simplicial complex, and let $\delta$ be a perversity (i.e., some function from integers to integers). One can consider two categories: (1) the category of perverse sheaves cohomologically constructible with…

Algebraic Topology · Mathematics 2007-05-23 Maxim Vybornov

The geometric Satake isomorphism is an equivalence between the categories of spherical perverse sheaves on affine Grassmanian and the category of representations of the Langlands dual group. We provide a similar description for derived…

Representation Theory · Mathematics 2020-02-13 Sergey Arkhipov , Roman Bezrukavnikov

Using combinatorial properties of symmetric polynomials, we compute explicitly the Soergel modules for some permutations whose corresponding Schubert varieties are rationally smooth. We build from them diagram algebras whose module…

Representation Theory · Mathematics 2013-11-28 Antonio Sartori

We describe categories of equivariant vector bundles on certain toroidal spherical varieties in linear algebra terms: vector spaces equipped with filtrations, group and Lie algebra actions, and linear maps preserving these structures.

Algebraic Geometry · Mathematics 2009-08-28 Aravind Asok , James Parson

In this paper we propose a construction of a monoidal category of "free-monodromic" tilting perverse sheaves on (Kac-Moody) flag varieties in the setting of the "mixed modular derived category" introduced by the first and third authors.…

Representation Theory · Mathematics 2022-11-15 Pramod N. Achar , Shotaro Makisumi , Simon Riche , Geordie Williamson

We generalize the higher Riemann-Hilbert correspondence in the presence of scalar curvature for a (possibly non-compact) smooth manifold $M$. We show that the dg-category of curved $\infty$-local systems, the dg-category of graded vector…

Algebraic Topology · Mathematics 2024-12-02 Patrick Antweiler

We exhibit a relationship between projective duality and the sheaf of logarithmic vector fields along a reduced divisor $D$ of projective space, in that the push-forward of the ideal sheaf of the conormal variety in the point-hyperplane…

Algebraic Geometry · Mathematics 2023-12-22 Vladimiro Benedetti , Daniele Faenzi , Simone Marchesi

The category O of BGG can be thought of as a category of sheaves over the flag variety F in the sense that the algebra E of self-extensions of the trivial object of O is isomorphic to the cohomology algebra of the flag variety. A…

Quantum Algebra · Mathematics 2009-07-22 Pierre-Yves Gaillard

We construct a categorification of the maximal commutative subalgebra of the type $A$ Hecke algebra. Specifically, we propose a monoidal functor from the (symmetric) monoidal category of coherent sheaves on the flag Hilbert scheme to the…

Geometric Topology · Mathematics 2022-10-26 Eugene Gorsky , Andrei Neguţ , Jacob Rasmussen

We introduce a new method for ``twisting'' relative equivalences of derived categories of sheaves on two spaces over the same base. The first aspect of this is that the derived categories of sheaves on the spaces are twisted. They become…

Algebraic Geometry · Mathematics 2015-02-16 Oren Ben-Bassat

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 formulate a version of Beck's monadicity theorem for abelian categories, which is applied to the equivariantization of abelian categories with respect to a finite group action. We prove that the equivariantization is compatible with the…

Rings and Algebras · Mathematics 2014-08-04 Jianmin Chen , Xiao-Wu Chen , Zhenqiang Zhou

We apply the equivariance --> families principle to a geometric family of Clifford module bundles with an action of a compact Lie group G to prove an equivariant version of Bismut's families index theorem on the differential Borel quotient…

Differential Geometry · Mathematics 2022-08-12 Richard Wedeen

A geometric extension algebra is an extension algebra of a semi-simple perverse sheaf (allowing shifts), e.g. a push-forward of the constant sheaf under a projective map. Particular nice situations arise for collapsings of homogeneous…

Representation Theory · Mathematics 2015-10-06 Julia Sauter

We study a version of the BGG category O for Dynkin Borel subalgebras of root-reductive Lie algebras g, such as gl(\infty). We prove results about extension fullness and compute the higher extensions of simple modules by Verma modules. In…

Representation Theory · Mathematics 2019-03-20 Kevin Coulembier , Ivan Penkov