English
Related papers

Related papers: Exact couples in semiabelian categories revisited

200 papers

This paper continues the research of the author on the homology of cubical and semi-cubical sets with coefficients in systems of objects. The main result is the theorem that the homology of cubical sets with coefficients in contravariant…

Algebraic Topology · Mathematics 2023-08-11 Ahmet A. Husainov

It is often the case that a Selmer group of an abelian variety and a group related to an ideal class group can both be naturally embedded into the same cohomology group. One hopes to compute one from the other by finding how close each is…

Number Theory · Mathematics 2015-07-31 Edward F. Schaefer

We use (non-)additive sheaves to introduce an (absolute) notion of Hochschild cohomology for exact categories as Ext's in a suitable bisheaf category. We compare our approach to various definitions present in the literature.

K-Theory and Homology · Mathematics 2011-04-19 Dmitry Kaledin , Wendy Lowen

We give an explicit formula for the Deligne pairing for a proper and flat morphisms $f:X\to S$ of schemes, in terms of the determinant of cohomology. The whole construction is justified by an analogy with the intersection theory on…

Algebraic Geometry · Mathematics 2021-06-14 Paolo Dolce

We extend Poincar\'e duality in \'etale cohomology from smooth schemes to regular ones. This is achieved via a formalism of trace maps for local complete intersection morphisms.

Algebraic Geometry · Mathematics 2024-09-24 Adeel A. Khan

A duality theorem of the bounded derived category of quasi-finite comodules over an artinian coalgebra is established. Let $A$ be a noetherian complete basic semiperfect algebra over an algebraically closed field, and $C$ be its dual…

Rings and Algebras · Mathematics 2010-10-07 J. -W. He , B. Torrecillas , F. Van Oystaeyen , Y. Zhang

We construct relative abelian categories in the sense of MacLane for models of algebraic systems in (co)complete abelian categories. As an example, we consider an analogue of Hochschild-Mitchell cohomology for the functor of Yoneda…

K-Theory and Homology · Mathematics 2017-06-20 Simeon Pol'shin

Proto-exact and parabelian categories serve as non-additive analogues of exact and quasi-abelian categories, respectively. They give rise to algebraic K-theory and Hall algebras similarly to the additive setting. We show that every…

Representation Theory · Mathematics 2025-03-11 Sergey Mozgovoy

We consider sequences of absolute and relative homology and cohomology groups that arise naturally for a filtered cell complex. We establish algebraic relationships between their persistence modules, and show that they contain equivalent…

Algebraic Topology · Mathematics 2015-05-28 Vin de Silva , Dmitriy Morozov , Mikael Vejdemo-Johansson

For certain manifolds with an involution the mod 2 cohomology ring of the set of fixed points is isomorphic to the cohomology ring of the manifold, up to dividing the degrees by two. Examples include complex projective spaces and…

Algebraic Topology · Mathematics 2007-05-23 Joost van Hamel

We establish a 6-term left exact sequence, involving Galois cohomology of the base field $\mathbb K$, and the Brauer-Picard groupoid of a fusion category. This generalizes a result of Etingof, Nikshych, and Ostrik to the setting where…

Quantum Algebra · Mathematics 2026-04-14 Sean Sanford

Several important types of categories have been shown to be both exact and coexact (in the sense of Barr). The first type consists of abelian categories, which due to their self-dual definition, can be seen to be both exact and coexact by…

Category Theory · Mathematics 2026-03-30 James Richard Andrew Gray

We prove that a certain homological epimorphism between two algebras induces a triangle equivalence between their singularity categories. Applying the result to a construction of matrix algebras, we describe the singularity categories of…

Rings and Algebras · Mathematics 2015-02-10 Xiao-Wu Chen

Hilbert bimodules are morphisms between C*-algebraic models of quantum systems, while symplectic dual pairs are morphisms between Poisson geometric models of classical systems. Both of these morphisms preserve representation-theoretic…

Mathematical Physics · Physics 2024-05-01 Benjamin H. Feintzeig , Jer Steeger

This paper is a coalgebra version of arXiv:1703.04266 and a sequel to arXiv:1607.03066. We present the definition of a pseudo-dualizing complex of bicomodules over a pair of coassociative coalgebras $\mathcal C$ and $\mathcal D$. For any…

Category Theory · Mathematics 2022-02-24 Leonid Positselski

Inspired by an experimental study of energy-minimizing periodic configurations in Euclidean space, Cohn, Kumar and Sch\"urmann proposed the concept of formal duality between a pair of periodic configurations, which indicates an unexpected…

Combinatorics · Mathematics 2018-11-06 Shuxing Li , Alexander Pott , Robert Schüler

We mainly investigate abelian quotients of the categories of short exact sequences. The natural framework to consider the question is via identifying quotients of morphism categories as modules categories. These ideas not only can be used…

Representation Theory · Mathematics 2018-02-13 Zengqiang Lin

We use relative group cohomologies to compute the Kac cohomology of matched pairs of finite groups. This cohomology naturally appears in the theory of abelian extensions of finite dimensional Hopf algebras. We prove that Kac cohomology can…

Quantum Algebra · Mathematics 2019-07-17 César Galindo , Yiby Morales

We develop a general theory of partial morphisms in additive exact categories which extends the model theoretic notion introduced by Ziegler in the particular case of pure-exact sequences in the category of modules over a ring. We relate…

Rings and Algebras · Mathematics 2020-03-11 Manuel Cortés-Izurdiaga , Pedro A. Guil Asensio , Berke Kalebogaz , Ashish K. Srivastava

As an example of the categorical apparatus of pseudo algebras over 2-theories, we show that pseudo algebras over the 2-theory of categories can be viewed as pseudo double categories with folding or as appropriate 2-functors into…

Category Theory · Mathematics 2011-11-09 Thomas M. Fiore