English
Related papers

Related papers: On purity theorem of Lusztig's perverse sheaves

200 papers

Let $X$ be a singular Hermitian complex space of pure dimension $n$. We use a resolution of singularities to give a smooth representation of the $L^2$-$\overline\partial$-cohomology of $(n,q)$-forms on $X$. The central tool is an…

Complex Variables · Mathematics 2015-11-03 Jean Ruppenthal

A consequence of the recent work of Ren and Zhu on Gorenstein projective dimensions of modules over Hopf algebras is that if $A$ and $B$ are Hopf algebras with bijective antipodes having equivalent linear tensor categories of comodules and…

K-Theory and Homology · Mathematics 2026-02-16 Julien Bichon

We relate the Fourier transform of perverse sheaves smooth along the coordinate hyperplane configuration in a complex vector space to the Deligne-Lusztig duality of unipotent representations of a general linear group over a finite field. A…

Representation Theory · Mathematics 2022-06-02 Michael Finkelberg , Alexander Postnikov , Vadim Schechtman

In this paper, we introduce a new class of $\ell$-adic sheaves, which we call quadratic $\ell$-adic sheaves, on connected unipotent commutative algebraic groups over finite fields. They are sheaf-theoretic enhancements of quadratic forms on…

Number Theory · Mathematics 2023-05-25 Daichi Takeuchi

Schubert varieties have been exhaustively studied with a plethora of techniques: Coxeter groups, explicit desingularization, Frobenius splitting, etc. Many authors have applied these techniques to various other varieties, usually defined by…

Algebraic Geometry · Mathematics 2007-05-23 Peter Magyar

We consider the localization $\mathcal{Q}_{\mathbf{V},\mathbf{W}}/\mathcal{N}_{\mathbf{V}}$ of Lusztig's sheaves for framed quivers, and define functors $E^{(n)}_{i},F^{(n)}_{i},K^{\pm}_{i},n\in \mathbb{N},i \in I$ between the…

Representation Theory · Mathematics 2025-03-18 Jiepeng Fang , Yixin Lan , Jie Xiao

Let ${\mathcal B}_{\mathfrak{q}}$ be a finite-dimensional Nichols algebra of diagonal type with braiding matrix $\mathfrak{q}$, let $\mathcal{L}_{\mathfrak{q}}$ be the corresponding Lusztig algebra as in arXiv:1501.04518 and let…

Quantum Algebra · Mathematics 2021-11-17 Nicolás Andruskiewitsch , Iván Angiono , Fiorela Rossi Bertone

Let H be a Hecke algebra arising as an endomorphism algebra of the representation of a Chevalley group G over F_q induced by a unipotent cuspidal representation of a Levi quotient L of a parabolic subgroup. We assume that L is not a torus.…

Representation Theory · Mathematics 2015-01-30 G. Lusztig

In two articles by Barthel, Brasselet, Fieseler and Kaup, and, Bressler and Lunts, a combinatorial theory of intersection cohomology and perverse sheaves has been developed on fans. In the first one, one tried to present everything on an…

Algebraic Geometry · Mathematics 2007-05-23 Karl-Heinz Fieseler

By introducing Frobenius morphisms $F$ on algebras $A$ and their modules over the algebraic closure ${{\bar \BF}}_q$ of the finite field $\BF_q$ of $q$ elements, we establish a relation between the representation theory of $A$ over ${{\bar…

Rings and Algebras · Mathematics 2007-05-23 Bangming Deng , Jie Du

We call a sheaf on an algebraic variety immaculate if it lacks any cohomology including the zero-th one, that is, if the derived version of the global section functor vanishes. Such sheaves are the basic tools when building exceptional…

Algebraic Geometry · Mathematics 2018-08-29 Klaus Altmann , Jarosław Buczyński , Lars Kastner , Anna-Lena Winz

In the present paper we prove that Hall polynomial exists for each triple of decomposition sequences which parameterize isomorphism classes of coherent sheaves of a domestic weighted projective line $\mathbb X$ over finite fields. These…

Representation Theory · Mathematics 2015-12-14 Bangming Deng , Shiquan Ruan

For a finite quiver without sources or sinks, we prove that the homotopy category of acyclic complexes of injective modules over the corresponding finite dimensional algebra with radical square zero is triangle equivalent to the derived…

Representation Theory · Mathematics 2015-12-09 Xiao-Wu Chen , Dong Yang

We study the vanishing cycles of a one-parameter smoothing of a complex analytic space and show that the weight filtration on its perverse cohomology sheaf of the highest degree is quite close to the monodromy filtration so that its graded…

Algebraic Geometry · Mathematics 2010-08-11 Alexandru Dimca , Morihiko Saito

We prove that a virtually periodic object in an abelian category gives rise to a non-vanishing result on certain Hom groups in the singularity category. Consequently, for any artin algebra with infinite global dimension, its singularity…

Representation Theory · Mathematics 2023-04-07 Xiao-Wu Chen , Zhi-Wei Li , Xiaojin Zhang , Zhibing Zhao

We prove that if X is a Grassmannian of type A, then the Schubert basis of the (small) quantum cohomology ring QH(X) is the only homogeneous deformation of the Schubert basis of the ordinary cohomology ring of X that multiplies with…

Algebraic Geometry · Mathematics 2019-05-15 Anders S. Buch , Chengxi Wang

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

We study Brou\'e's abelian defect group conjecture for groups of Lie type using the recent theory of perverse equivalences and Deligne--Lusztig varieties. Our approach is to analyze the perverse equivalence induced by certain…

Representation Theory · Mathematics 2012-07-03 David A. Craven

Let $X$ be a regular scheme over $\textrm{Spec}(\mathbb{Z}[1/p])$ where $p$ is prime. Let $i:Y\to X$ be a closed subscheme of pure codimension $r$. Let $n$ be a natural number prime to $p$. Let $\Lambda$ be a finite $\mathbb{Z}/n$-module…

Algebraic Geometry · Mathematics 2024-08-06 Amine Koubaa

This article presents a formula for products of Schubert classes in the quantum cohomology ring of the Grassmannian. We introduce a generalization of Schur symmetric polynomials for shapes that are naturally embedded in a torus. Then we…

Combinatorics · Mathematics 2007-05-23 Alexander Postnikov