English
Related papers

Related papers: Nonabelian Algebraic Topology

200 papers

We prove an extension of the nonabelian Hodge theorem in which the underlying objects are twisted torsors over a smooth complex projective variety. In the prototypical case of $GL_n$-torsors, one side of this correspondence consists of…

Complex Variables · Mathematics 2015-01-26 Alberto Garcia-Raboso

Topological T-duality is a transformation taking a gerbe on a principal torus bundle to a gerbe on a principal dual-torus bundle. We give a new geometric construction of T-dualization, which allows the duality to be extended in following…

Quantum Algebra · Mathematics 2007-10-07 Calder Daenzer

We discuss various lifting and reduction problems for bundles and gerbes in the context of a strict Lie 2-group. We obtain a geometrical formulation (and a new proof) for the exactness of Breen's long exact sequence in non-abelian…

Algebraic Topology · Mathematics 2013-05-10 Thomas Nikolaus , Konrad Waldorf

I dedicated the volume $1$ of monograph 'Introduction into Noncommutative Algebra' to studying of algebra over commutative ring. The main topics that I covered in this volume: definition of module and algebra over commutative ring; linear…

General Mathematics · Mathematics 2024-05-24 Aleks Kleyn

This paper is a sequel to arXiv:2307.13358 and arXiv:2308.16090. A construction associating a semialgebra with an algebra, subalgebra, and a coalgebra dual to the subalgebra played a central role in the author's book arXiv:0708.3398. In…

Category Theory · Mathematics 2023-10-10 Leonid Positselski

We construct a representation of the blob algebra over a ring allowing base change to every interesting (i.e. non--semisimple) specialisation which, in quasihereditary specialisations, passes to a full tilting module.

Representation Theory · Mathematics 2007-05-23 P P Martin , S Ryom-Hansen

Lecture notes of an algebraic geometry graduate course. The topics covered are as follows. Cohomology: ext sheaves and groups, cohomology with support, local cohomology, local duality. Duality: relative duality, Cohen-Macaulay schemes.…

Algebraic Geometry · Mathematics 2011-04-28 Caucher Birkar

This a slightly expended version of my habilitation thesis, which is an overview of my research activities during the last 4 years, written in a rather informal style.

Algebraic Geometry · Mathematics 2007-05-23 Betrand Toen

We study non-abelian differentiable gerbes over stacks using the theory of Lie groupoids. More precisely, we develop the theory of connections on Lie groupoid $G$-extensions, which we call "connections on gerbes", and study the induced…

Differential Geometry · Mathematics 2009-03-20 Camille Laurent-Gengoux , Mathieu Stienon , Ping Xu

This paper builds a general framework in which to study cohomology theories of strongly homotopy algebras, namely $A_\infty, C_\infty$ and $L_\infty$-algebras. This framework is based on noncommutative geometry as expounded by Connes and…

Quantum Algebra · Mathematics 2014-10-01 Alastair Hamilton , Andrey Lazarev

In this paper we extend and adapt several results on extensions of Lie algebras to topological Lie algebras over topological fields of characteristic zero. In particular we describe the set of equivalence classes of extensions of the Lie…

Rings and Algebras · Mathematics 2007-05-23 Karl-Hermann Neeb

We give a construction of cyclic cocycles on convolution algebras twisted by gerbes over discrete translation groupoids. For proper \'etale groupoids, Tu and Xu provide a map between the periodic cyclic cohomology of a gerbe-twisted…

Quantum Algebra · Mathematics 2015-05-27 Eitan Angel

For a class of pointed Hopf algebras including the quantized enveloping algebras, we discuss cleft extensions, cocycle deformations and the second cohomology. We present such a non-standard method of computing the abelian second cohomology…

Quantum Algebra · Mathematics 2008-04-21 Akira Masuoka

In the context of non-abelian gerbes we define a cubical version of categorical group 2-bundles with connection over a smooth manifold. We define their two-dimensional parallel transport, study its properties, and define non-abelian Wilson…

Category Theory · Mathematics 2010-01-26 Joao Faria Martins , Roger Picken

This paper surveys results on the connections between the cohomology for algebraic groups, finite groups and Frobenius kernels that were presented at the Workshop and Summer School on Lie and Representation Theory at East China Normal…

Group Theory · Mathematics 2014-04-15 Daniel K. Nakano

Let $f:X\to Y$ be a finite ramified Galois covering of algebraic varieties defined over the complex numbers. In this paper, we prove some structure theorems for such coverings in the case that the non-abelian Galois group of the cover is…

Algebraic Geometry · Mathematics 2019-12-24 Abolfazl Mohajer

The notion of a \emph{higher-order algebroid}, as introduced by J\'o\'zwikowski and Rotkiewicz in their work \emph{Higher-order analogs of Lie algebroids via vector bundle comorphisms} (SIGMA, 2018), generalizes the concepts of a…

Differential Geometry · Mathematics 2024-10-01 Mikołaj Rotkiewicz

We provide new, improved lower bounds for the Hodge and Frobenius colevels of algebraic varieties (over $\mathbf{C}$ or over a finite field) in all cohomological degrees. These bounds are expressed in terms of the dimension of the variety…

Algebraic Geometry · Mathematics 2025-04-23 Daqing Wan , Dingxin Zhang

In this paper we study non-abelian extensions of a Lie group $G$ modeled on a locally convex space by a Lie group $N$. The equivalence classes of such extension are grouped into those corresponding to a class of so-called smooth outer…

Group Theory · Mathematics 2007-05-23 Karl-Hermann Neeb

In this article we study higher homological properties of $n$-levelled algebras and connect them to properties of the underlying graphs. Notably, to each $2$-representation-finite quadratic monomial algebra $\Lambda$ we associate a…

Representation Theory · Mathematics 2024-11-04 Karin M. Jacobsen , Mads Hustad Sandøy , Laertis Vaso