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Related papers: Difference sheaves and torsors

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In [1] we introduced the concept of structured space, which is a topological space that locally resembles some algebraic structures. In [2] we proceeded the study of these spaces, developing two cohomology theories. The aim of this paper is…

Algebraic Topology · Mathematics 2020-04-28 Manuel Norman

We describe algorithms based on invariant theory to solve problems on the geometry of curves, mainly those of genus 2, 3 and 4. New theoretical results building on the first author's PhD thesis are also included.

Algebraic Geometry · Mathematics 2026-03-11 Thomas Bouchet , Reynald Lercier , Jeroen Sijsling , Christophe Ritzenthaler

We construct algorithms and topological invariants that allow us to distinguish the topological type of a surface, as well as functions and vector fields for their topological equivalence. In the first part (arXiv:2501.15657), we discused…

Geometric Topology · Mathematics 2025-02-17 Alexandr Prishlyak

This paper provides an overview of the applications of sheaf theory in deep learning, data science, and computer science in general. The primary text of this work serves as a friendly introduction to applied and computational sheaf theory…

Algebraic Topology · Mathematics 2025-02-24 Anton Ayzenberg , Thomas Gebhart , German Magai , Grigory Solomadin

We study differential forms and their higher-order generalizations by interpreting them as functions on map spaces. We get a series of approximations of "generalized manifolds" (i.e. of sheaves and stacks) somewhat akin to Taylor series.

Differential Geometry · Mathematics 2007-05-23 Pavol Severa

We introduce the formalism of differential conformal superalgebras, which we show leads to the "correct" automorphism group functor and accompanying descent theory in the conformal setting. As an application, we classify forms of N=2 and…

Rings and Algebras · Mathematics 2008-05-29 Victor Kac , Michael Lau , Arturo Pianzola

Coalgebra-Galois extensions generalise Hopf-Galois extensions, which can be viewed as non-commutative torsors. In this paper it is analysed when a coalgebra-Galois extension is a separable, split, or strongly separable extension.

Quantum Algebra · Mathematics 2007-05-23 Tomasz Brzezinski

In this paper, We develop the stratified de Rham theory on singular spaces using modern tools including derived geometry and stratified structures. This work unifies and extends the de Rham theory, Hodge theory, and deformation theory of…

Algebraic Geometry · Mathematics 2025-08-05 Jiaming Luo , Shirong Li

We introduce non-abelian cohomology sets of Hopf algebras with coefficients in Hopf modules. We prove that these sets generalize Serre's non-abelian group cohomology theory. Using descent techniques, we establish that our construction…

K-Theory and Homology · Mathematics 2007-05-23 Philippe Nuss , Marc Wambst

We study a derived version of Laumon's homogeneous Fourier transform, which exchanges G_m-equivariant sheaves on a derived vector bundle and its dual. In this context, the Fourier transform exhibits a duality between derived and stacky…

Algebraic Geometry · Mathematics 2024-10-10 Adeel A. Khan

In this article, we introduce a new cohomology theory associated to a Lie 2-algebras. This cohomology theory is shown to extend the classical cohomology theory of Lie algebras; in particular, we show that the second cohomology group…

Category Theory · Mathematics 2022-08-25 Camilo Angulo

Braided non-commutative differential geometry is studied. In particular we investigate the theory of (bicovariant) differential calculi in braided abelian categories. Previous results on crossed modules and Hopf bimodules in braided…

q-alg · Mathematics 2008-02-03 Yuri Bespalov , Bernhard Drabant

This paper introduces cellular sheaf theory to graphical methods and reciprocal constructions in structural engineering. The elementary mechanics and statics of trusses are derived from the linear algebra of sheaves and cosheaves. Further,…

Algebraic Topology · Mathematics 2023-11-23 Zoe Cooperband , Robert Ghrist , Jakob Hansen

Distributions, i.e., subsets of tangent bundles formed by piecing together subspaces of tangent spaces, are commonly encountered in the theory and application of differential geometry. Indeed, the theory of distributions is a fundamental…

Differential Geometry · Mathematics 2023-09-20 Andrew D. Lewis

The differential geometry on a Hopf algebra is constructed, by using the basic axioms of Hopf algebras and noncommutative differential geometry. The space of generalized derivations on a Hopf algebra of functions is presented via the smash…

High Energy Physics - Theory · Physics 2008-02-03 Paul Watts

Informal lecture notes with examples on sheaf theory and the derived category of sheaves; sheaves and Morse theory; perverse sheaves, and some applications to representation theory. Added Oct 2021: cellular perverse sheaves. Proofs are…

Algebraic Geometry · Mathematics 2021-10-12 Mark Goresky

We consider differential forms associated to Campana's geometric orbifolds from a new perspective, namely, as a qfh-sheaf on the variety underlying the geometric orbifold. This approach avoids having to choose a covering of the underlying…

Algebraic Geometry · Mathematics 2023-07-06 Pedro Núñez

We propose a sheaf-theoretic approach to the theory of differential calculi on quantum principal bundles over non-affine bases. After recalling the affine case we define differential calculi on sheaves of comodule algebras as sheaves of…

Quantum Algebra · Mathematics 2023-02-07 P. Aschieri , R. Fioresi , E. Latini , T. Weber

This paper defines and examines the basic properties of noncommutative analogues of almost complex structures, integrable almost complex structures, holomorphic curvature, cohomology, and holomorphic sheaves. The starting point is a…

Algebraic Geometry · Mathematics 2013-03-07 Edwin Beggs , S. Paul Smith

These course note first provide an introduction to secondary characteristic classes and differential cohomology. They continue with a presentation of a stable homotopy theoretic approach to the theory of differential extensions of…

Algebraic Topology · Mathematics 2013-08-20 Ulrich Bunke