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Related papers: Generic character sheaves on parahoric subgroups

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Let $K/F$ be a quadratic extension of p-adic fields. The Bernstein-Zelevinsky's classification asserts that generic representations are parabolically induced from quasi-square-integrable representations. We show, following a method…

Representation Theory · Mathematics 2009-01-02 Nadir Matringe

Building on a geometric counterpart of Steinberg's tensor product formula for simple representations of a connected reductive algebraic group $G$ over a field of positive characteristic, and following an idea of…

Representation Theory · Mathematics 2024-03-26 Pramod N. Achar , Simon Riche

For a finite central extension $\tilde{G}$ of a classical $p$-adic reductive group, we consider the endomorphism algebra of some induced projective generator \`a la Bernstein of the category of smooth representations of $\tilde{G}$. In the…

Representation Theory · Mathematics 2025-08-07 Volker Heiermann , Chenyan Wu

In this paper we continue the study of character sheaves on a reductive group G. To each subset of the set of simple reflections in the Weyl group we associate an algebra of the same kind as an Iwahori-Hecke algebra with unequal parameters…

Representation Theory · Mathematics 2007-05-23 G. Lusztig

To a torus action on a complex vector space, Gelfand, Kapranov and Zelevinsky introduce a system of differential equations, called the GKZ hypergeometric system. Its solutions are GKZ hypergeometric functions. We study the $\ell$-adic…

Algebraic Geometry · Mathematics 2016-04-27 Lei Fu

We show that there is a perverse sheaf on a fine moduli space of stable sheaves on a smooth projective Calabi-Yau 3-fold, which is locally the perverse sheaf of vanishing cycles for a local Chern-Simons functional, possibly after taking an…

Algebraic Geometry · Mathematics 2016-03-22 Young-Hoon Kiem , Jun Li

We analyze irreducible perverse sheaves on abelian varieties, defined over the complex numbers or the algebraic closure of a finite field, whose Euler characteristic is zero. We give a description of such perverse sheaves under assumptions…

Algebraic Geometry · Mathematics 2015-10-27 Rainer Weissauer

Let Q be an affine quiver of type A. Let C be the associated generalized Cartan matrix. Let U^- be the negative part of the quantized enveloping algebra attached to C. In terms of perverse sheaves on the moduli space of representations of a…

Quantum Algebra · Mathematics 2007-05-23 Yiqiang Li

We relate Nakajima Quiver Varieties (or, rather, their multiplicative version) with moduli spaces of perverse sheaves. More precisely, we consider a generalization of the concept of perverse sheaves: microlocal sheaves on a nodal curve X.…

Symplectic Geometry · Mathematics 2015-06-30 Roman Bezrukavnikov , Mikhail Kapranov

We prove very general formulae for the generating series of (Hodge) genera of symmetric products with coefficients, which hold for complex quasi-projective varieties with any kind of singularities, and which include many of the classical…

Algebraic Geometry · Mathematics 2012-04-03 Laurentiu Maxim , Joerg Schuermann

We show that certain categories of perverse sheaves on a pair of affine toric varieties defined by dual cones are Koszul dual in the sense of Beilinson, Ginzburg and Soergel. The functor expressing this duality is constructed explicitly…

Algebraic Geometry · Mathematics 2007-05-23 Tom Braden

We give a description of certain categories of equivariant coherent sheaves on Grothendieck's resolution in terms of the categorical affine Hecke algebra of Soergel. As an application, we deduce a relationship of these coherent sheaf…

Algebraic Geometry · Mathematics 2011-08-22 Christopher Dodd

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 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

We prove that every Grothendieck topology induces a hereditary torsion pair in the category of presheaves of modules on a ringed site, and obtain a homological characterization of sheaves of modules: a presheaf of modules is a sheaf of…

Representation Theory · Mathematics 2025-07-30 Zhenxing Di , Liping Li , Li Liang

We construct a new isomorphism between the endomorphism algebra of an induced cuspidal character sheaf and the group algebra of the relative Weyl group involved. We show it differs from Lusztig one by a linear character, and we relate this…

Group Theory · Mathematics 2007-05-23 Cedric Bonnafe

Given a smooth projective toric variety $X_\Sigma$ of complex dimension $n$, Fang-Liu-Treumann-Zaslow \cite{FLTZ} showed that there is a quasi-embedding of the differential graded (dg) derived category of coherent sheaves $Coh(X_\Sigma)$…

Algebraic Geometry · Mathematics 2017-01-04 Peng Zhou

We show that compatible systems of $\ell$-adic sheaves on a scheme of finite type over the ring of integers of a local field are compatible along the boundary up to stratification. This extends a theorem of Deligne on curves over a finite…

Algebraic Geometry · Mathematics 2019-11-13 Qing Lu , Weizhe Zheng

We generalise to the equivariant case a result of J. Denef and F. Loeser about trigonometric sums on tori; on the other hand, we study the Thom-Boardman stratification associated to the multiplication of global sections of line bundles on a…

Algebraic Geometry · Mathematics 2020-02-04 Lizao Ye

In this paper we classify and give Kazhdan-Lusztig type character formulas for equivariantly irreducible representations of Lie algebras of reductive algebraic groups over a field of large positive characteristic. The equivariance is with…

Representation Theory · Mathematics 2020-11-17 Roman Bezrukavnikov , Ivan Losev