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Related papers: Equivariant homology of stacks

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We present a version of higher Hochschild homology for spaces equipped with principal bundles for a structure group $G$. As coefficients, we allow $E_\infty$-algebras with $G$-action. For this homology theory, we establish an equivariant…

Algebraic Topology · Mathematics 2019-05-13 Lukas Müller , Lukas Woike

Let $\Delta$ be a trivial knot in the three-sphere. For every finite cyclic group $G$ of odd order, we construct a $G$-equivariant Khovanov homology with coefficients in the filed $\F_{2}$. This homology is an invariant of links up to…

Geometric Topology · Mathematics 2007-05-23 Nafaa Chbili

In the paper we answer the following question: for a morphism of varieties (or, more generally, stacks), when the derived category of the base can be recovered from the derived category of the covering variety by means of descent theory? As…

Algebraic Geometry · Mathematics 2015-05-27 Alexey Elagin

We give a homotopy theoretic characterization of stacks on a site $\cC$ as the {\it homotopy sheaves} of groupoids on $\cC$. We use this characterization to construct a model category in which stacks are the fibrant objects. We compare…

Algebraic Topology · Mathematics 2007-08-20 Sharon Hollander

We introduce an equivariant version of Hochschild cohomology as the deformation cohomology to study equivariant deformations of associative algebras equipped with finite group actions.

Rings and Algebras · Mathematics 2018-04-17 Goutam Mukherjee , Raj Bhawan Yadav

We use a well known problem in discrete and computational geometry (partitions of measures by $k$-fans) as a motivation and as a point of departure to illustrate many aspects, both theoretical and computational, of the problem of…

Algebraic Topology · Mathematics 2007-05-23 Pavle V. M. Blagojevic , Sinisa T. Vrecica , Rade T. Zivaljevic

We study the cohomology of $G$-representation varieties and $G$-character stacks by means of a topological quantum field theory (TQFT). This TQFT is constructed as the composite of a so-called field theory and the 6-functor formalism of…

Algebraic Geometry · Mathematics 2024-07-01 Jesse Vogel

We define and study bivariant equivariant periodic cyclic homology for actions of ample groupoids. In analogy to the group case, we show that the theory satisfies homotopy invariance, stability, and excision in both variables. We also prove…

K-Theory and Homology · Mathematics 2026-02-20 Francesco Pagliuca , Christian Voigt

We study the homotopy theory of locally ordered spaces, that is manifolds with boundary whose charts are partially ordered in a compatible way. Their category is not particularly well-behaved with respect to colimits. However, this category…

Algebraic Topology · Mathematics 2009-12-21 Krzysztof Worytkiewicz

We introduce an equivariant version of contextuality with respect to a symmetry group, which comes with natural applications to quantum theory. In the equivariant setting, we construct cohomology classes that can detect contextuality. This…

Quantum Physics · Physics 2023-10-30 Cihan Okay , Igor Sikora

We describe the E-infinity algebra structure on the complex of singular cochains of a topological space, in the context of sheaf theory. As a first application, for any algebraic variety we define a weight filtration compatible with its…

Algebraic Topology · Mathematics 2022-02-14 David Chataur , Joana Cirici

We motivate and survey the theory of BPS invariants of categories and BPS cohomology of stacks, indicating applications in enumerative geometry and representation theory, as well as recent advances.

Algebraic Geometry · Mathematics 2026-01-14 Ben Davison

An equivariant topological field theory is defined on a cobordism category of manifolds with principal fiber bundles for a fixed (finite) structure group. We provide a geometric construction which for any given morphism $G \to H$ of finite…

Quantum Algebra · Mathematics 2018-10-22 Christoph Schweigert , Lukas Woike

A homology and cohomology theory for topological quandles are introduced. The relation between these (co)homology groups and quandle (co)homology groups are studied. The 1 - topological quandle cocycles are used to compute state sum…

Geometric Topology · Mathematics 2022-08-03 Georgy C. Luke , B. Subhash

We describe a symmetry breaking construction in coarse geometry which allows to obtain information about equivariant coarse homology classes by restriction to smaller groups and spaces. In the case of equivariant coarse $K$-homology theory…

Algebraic Topology · Mathematics 2025-04-01 Ulrich Bunke , Matthias Ludewig

Recently, the authors of this paper introduced logarithmic Hochschild (co)homology of logarithmic spaces in a geometric way using formality of derived intersections. In this paper, the authors extend the decomposition theorem for the…

Algebraic Geometry · Mathematics 2026-04-15 Marton Hablicsek , Leo Herr , Francesca Leonardi

In this paper, we define a new cohomology theory for multiplicative Hom-pre-Lie algebras which controls deformations of Hom-pre-Lie algebra structure. This new cohomology is a natural one by considering the structure map. We develop…

Rings and Algebras · Mathematics 2023-08-01 Shuangjian Guo , Ripan Saha

Despite a blossoming of research activity on racks and their homology for over two decades, with a record of diverse applications to central parts of contemporary mathematics, there are still very few examples of racks whose homology has…

Algebraic Topology · Mathematics 2025-07-03 Victoria Lebed , Markus Szymik

In this note I introduce a new approach to (or rather a new language for) representation theory of groups. Namely, I propose to consider a (complex) representation of a group $G$ as a sheaf on some geometric object (a stack). This point of…

Representation Theory · Mathematics 2016-05-13 Joseph Bernstein

In the theory of configuration spaces, "splitting" usually refers to the phenomenon that the configuration spaces on a manifold and those on its punctured version are closely related cohomologically. We prove a splitting theorem that is…

Algebraic Geometry · Mathematics 2024-05-01 Yifeng Huang