English
Related papers

Related papers: Homotopy cartesian squares in extriangulated categ…

200 papers

Let X=G/K be a connected Riemannian homogeneous space of a real Lie group G. The homogeneous space X is called commutative if the algebra of G-invariant differential operators on X is commutative. We prove an effective commutativity…

Representation Theory · Mathematics 2007-05-23 Oksana Yakimova

Higher Homotopy van Kampen Theorems allow the computation as colimits of certain homotopical invariants of glued spaces. One corollary is to describe homotopical excision in critical dimensions in terms of induced modules and crossed…

Algebraic Topology · Mathematics 2013-10-15 Ronald Brown , Rafael Sivera

We here construct an explicit isomorphism between any commutative Hopf algebra which underlying coalgebra is the tensor coalgebra of a space $V$ and the shuffle algebra based on the same space. This isomorphism uses the commutative…

Combinatorics · Mathematics 2024-03-14 Loïc Foissy , Frédéric Patras

In this work we introduce the notion of higher $\mathbb{E}$-extension groups for an extriangulated category $\mathcal{C}$ and study the quotients $\mathcal{X}_{n+1}^{\vee}/[\mathcal{X}]$ and $\mathcal{X}_{n+1}^{\wedge}/[\mathcal{X}]$ when…

Representation Theory · Mathematics 2023-09-27 Mindy Y. Huerta , Octavio Mendoza , Corina Sáenz , Valente Santiago

The sectional category of a subgroup inclusion $H \hookrightarrow G$ can be defined as the sectional category of the corresponding map between Eilenberg--MacLane spaces. We extend a characterization of topological complexity of aspherical…

Algebraic Topology · Mathematics 2023-12-13 Zbigniew Błaszczyk , José Carrasquel , Arturo Espinosa Baro

Beligiannis and Marmaridis [\emph{Comm. in Algebra,} 22(12)(1994), 5021-5036] constructed the left and right triangulated structures on the stable categories of additive categories induced from some homological finite subcategories. We…

Category Theory · Mathematics 2014-02-11 Zhi-Wei Li

We show that the notions of homotopy epimorphism and homological epimorphism in the category of differential graded algebras are equivalent. As an application we obtain a characterization of acyclic maps of topological spaces in terms of…

Algebraic Topology · Mathematics 2021-06-15 Joe Chuang , Andrey Lazarev

A reductive homogeneous space $G/H$ is always diffeomorphic to the normal bundle of an orbit of a maximal compact subgroup of $G$. We prove that if $G/H$ admits compact quotients, then the sphere bundle associated to this normal bundle is…

Geometric Topology · Mathematics 2026-01-12 Fanny Kassel , Yosuke Morita , Nicolas Tholozan

By homotopy linear algebra we mean the study of linear functors between slices of the $\infty$-category of $\infty$-groupoids, subject to certain finiteness conditions. After some standard definitions and results, we assemble said slices…

Category Theory · Mathematics 2018-04-20 Imma Gálvez-Carrillo , Joachim Kock , Andrew Tonks

Let $R$ be a commutative ring If $\mathcal{C}_1$ and $\mathcal{C}_2$ are $R$-linear triangulated categories then we can give an obvious triangulated structure on $\mathcal{C} = \mathcal{C}_1 \oplus \mathcal{C}_2$ where $Hom_\mathcal{C}(U,…

Commutative Algebra · Mathematics 2024-04-30 Tony J. Puthenpurakal

This is mostly an overview. Given finitely presentable abelian categories $A$ and $B$, we sketch the construction of an abelian category of continuous functors from $A$ to $B$ that has nice $2$-categorical behaviour and gives an explicit…

Category Theory · Mathematics 2022-05-18 D. Kaledin

The question of the existence of Universal homotopy commutative and homotopy associative H-spaces (called Abelian H-spaces) is studied. Such a space T(X) would prolong a map from X into an Abelian H-space to a unique H-map from T into X.…

Algebraic Topology · Mathematics 2011-02-07 Brayton Gray

2-Theories are a canonical way of describing categories with extra structure. 2-theory-morphisms are used when discussing how one structure can be replaced with another structure. This is central to categorical coherence theory. We place a…

Category Theory · Mathematics 2007-05-23 Noson S. Yanofsky

The results of a previous paper on the equivariant homotopy theory of crossed complexes are generalised from the case of a discrete group to general topological groups. The principal new ingredient necessary for this is an analysis of…

Algebraic Topology · Mathematics 2016-08-15 R Brown , M Golasiński , T Porter , A Tonks

To characterize categorical constraints - associativity, commutativity and monoidality - in the context of quasimonoidal categories, from a cohomological point of view, we define the notion of a parity (quasi)complex. Applied to groups…

Category Theory · Mathematics 2007-05-23 Lucian M. Ionescu

We demonstrate that companionships and conjunctions in double $\infty$-categories -- and more generally, in double Segal spaces -- extend to functors out of the free-living companionship and conjunction respectively. Specifically, we prove…

Category Theory · Mathematics 2025-04-09 Jaco Ruit

We show that the two models of extensional type theory, those given by the category of equilogical spaces and by the effective topos, are homotopical quotients of categories of 2-groupoids.

Category Theory · Mathematics 2015-12-01 Giuseppe Rosolini

We compare the structure of a mapping cone in the category Top^D of spaces under a space D with differentials in algebraic models like crossed complexes and quadratic complexes. Several subcategories of Top^D are identified with algebraic…

Algebraic Topology · Mathematics 2010-05-27 Hans-Joachim Baues , Beatrice Bleile

For every regular cardinal $\alpha$, we construct a cofibrantly generated Quillen model structure on a category whose objects are essentially DG categories which are stable under suspensions, cosuspensions, cones and $\alpha$-small sums.…

K-Theory and Homology · Mathematics 2007-05-23 Goncalo Tabuada

We classify the homogeneous finite-dimensional permutation structures, i.e., homogeneous structures in a language of finitely many linear orders, giving a nearly complete answer to a question of Cameron, and confirming the classification…

Logic · Mathematics 2020-02-26 Samuel Braunfeld , Pierre Simon