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Related papers: Perverse Schobers

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We study a class of perverse sheaves on the variety of pairs (P,gU_P) where P runs through a conjugacy class of parabolics in a connected reductive group G and gU_P runs through G/U_P. This is a generalization of the theory of character…

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

In the framework of Abstract Differential Geometry, we show that to a given principal sheaf and a representation of its stuctural sheaf in $A^n$, where A is a sheaf of associative, commutative, unital algebras (over R or C), we associate a…

Differential Geometry · Mathematics 2013-05-29 E. Vassiliou

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

In this article, we introduce and study the concept of $\textit{spherical-vectors}$, which can be perceived as a natural extension of the arguments of complex numbers in the context of quaternions. We initially establish foundational…

Rings and Algebras · Mathematics 2023-05-09 Lahcen Lamgouni

We want to replace categories, functors and natural transformations by categories, open functors and open natural transformations. In analogy with open dynamical systems, the adjective open is added here to mean that some external…

Category Theory · Mathematics 2021-02-17 Alexandre Fernandez , Luidnel Maignan , Antoine Spicher

Reversible computing models settings in which all processes can be reversed. Applications include low-power computing, quantum computing, and robotics. It is unclear how to represent side-effects in this setting, because conventional…

Logic in Computer Science · Computer Science 2018-12-19 Chris Heunen , Robin Kaarsgaard , Martti Karvonen

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 develop some foundations of commutative algebra, with a view towards algebraic geometry, in symmetric tensor categories. Most results establish analogues of classical theorems, in tensor categories which admit a tensor functor to some…

Category Theory · Mathematics 2026-02-20 Kevin Coulembier

We characterize bifurcation values of polynomial functions by using the theory of perverse sheaves and their vanishing cycles. In particular, by introducing a method to compute the jumps of the Euler characteristics with compact support of…

Algebraic Geometry · Mathematics 2019-03-13 Kiyoshi Takeuchi

The purpose of this article is to set foundations for decomposition numbers of perverse sheaves, to give some methods to calculate them in simple cases, and to compute them concretely in two situations: for a simple (Kleinian) surface…

Algebraic Geometry · Mathematics 2013-09-24 Daniel Juteau

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

An intrinsic construction of the tensor category of finite dimensional representations of the Langlands dual group of G in terms of a tensor category of perverse sheaves on the loop group, LG, is given. The construction is applied to the…

alg-geom · Mathematics 2008-02-03 Victor Ginzburg

A categorical framework for modeling and analyzing systems in a broad sense is proposed. These systems should be thought of as `machines' with inputs and outputs, carrying some sort of signal that occurs through some notion of time. Special…

Category Theory · Mathematics 2019-03-18 Patrick Schultz , David I. Spivak , Christina Vasilakopoulou

Tangent categories are categories equipped with a tangent functor: an endofunctor with certain natural transformations which make it behave like the tangent bundle functor on the category of smooth manifolds. They provide an abstract…

Category Theory · Mathematics 2017-03-10 J. R. B. Cockett , G. S. H. Cruttwell

In this article, we continue our study of category dynamical systems, that is functors $s$ from a category $G$ to $\Top^{\op}$, and their corresponding skew category algebras. Suppose that the spaces $s(e)$, for $e \in \ob(G)$, are compact…

Rings and Algebras · Mathematics 2013-02-11 Patrik Lundström , Johan Öinert

In this paper, we study a new operation named pushforward on diffeological vector pseudo-bundles, which is left adjoint to the pullback. We show how to pushforward projective diffeological vector pseudo-bundles to get projective…

Differential Geometry · Mathematics 2022-05-20 Enxin Wu

For a large class of geometric objects, the passage to categories of quasi-coherent sheaves provides an embedding in the 2-category of abelian tensor categories. The notion of weakly Tannakian categories introduced by the author gives a…

Algebraic Geometry · Mathematics 2018-05-10 Daniel Schäppi

We show how the categorial approach to inverse monoids can be described as a certain endofunctor (which we call the partialization functor) of some category. In this paper we show that this functor can be used to obtain several recently…

Group Theory · Mathematics 2010-04-02 Ganna Kudryavtseva , Volodymyr Mazorchuk

A real vector space combined with an inverse for vectors is sufficient to define a vector continued fraction whose parameters consist of vector shifts and changes of scale. The choice of sign for different components of the vector inverse…

Mathematical Physics · Physics 2009-11-10 Roger Haydock , C. M. M. Nex , Geoffrey Wexler

We study the arithmetic Fourier transforms of trace functions on general connected commutative algebraic groups. To do so, we first prove a generic vanishing theorem for twists of perverse sheaves by characters, and using this tool, we…

Number Theory · Mathematics 2025-09-09 Arthur Forey , Javier Fresán , Emmanuel Kowalski