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We show that, for a right exact functor from an abelian category to abelian groups, Yoneda's isomorphism commutes with homology and, hence, with functor derivation. Then we extend this result to semiabelian domains. An interpretation in…

K-Theory and Homology · Mathematics 2017-11-09 George Peschke , Tim Van der Linden

In this paper, we formulate and prove a derived category version of Poitou-Tate duality on Galois cohomology of compact modules (with a continuous Galois action) over a pro-p ring, where p is a prime.

Number Theory · Mathematics 2012-12-24 Meng Fai Lim

This chapter sets out preliminaries for the duality theory in later chapters. An underlying idea is that local cohomology functors are higher derived functors of colocalizations (a.k.a.~coreflections). Predominantly well-known facts about…

Algebraic Geometry · Mathematics 2021-06-15 Joseph Lipman

This is a study of algebras with involution that become isomorphic over a separable closure of the base field to a tensor product of two composition algebras. We classify these algebras, provide criteria for isomorphism and isotopy, and…

Rings and Algebras · Mathematics 2021-12-20 Simon W. Rigby

In a previous paper [CG], we showed how one could generalize Taylor-Wiles modularity lifting theorems [Wil95, TW95] to contexts beyond those in which the automorphic forms in question arose from the middle degree cohomology of Shimura…

Number Theory · Mathematics 2017-07-18 Frank Calegari , David Geraghty

In this paper, we investigate non-abelian extensions of Lie algebras with derivations using several different approaches. We show that the theory of non-abelian extensions of a Lie algebra with a derivation can be characterized by means of…

Rings and Algebras · Mathematics 2026-04-30 Jun Jiang , Kanghe Xu

We introduce Hochschild (co-)homology of morphisms of schemes or analytic spaces and study its fundamental properties. In analogy with the cotangent complex we introduce the so called (derived) Hochschild complex of a morphism; the…

Algebraic Geometry · Mathematics 2007-05-23 R. -O. Buchweitz , H. Flenner

A general method for establishing results over a commutative complete intersection local ring by passing to differential graded modules over a graded exterior algebra is described. It is used to deduce, in a uniform way, results on the…

Commutative Algebra · Mathematics 2010-03-30 Luchezar L. Avramov , Srikanth B. Iyengar

The aim of this paper is to study the cohomology theory of Reynolds Lie algebras equipped with derivations and to explore related applications. We begin by introducing the concept of Reynolds LieDer pairs. Subsequently, we construct the…

Rings and Algebras · Mathematics 2025-04-24 Basdouri Imed , Sadraoui Mohamed Amin

We give an explicit description of the category of central extensions of a group scheme by a sheaf of Abelian groups. Based on this, we describe a framework for computing with central extensions of finite commutative group schemes, torsors…

Algebraic Geometry · Mathematics 2022-07-26 Peter Bruin

An abelian arrangement is a finite set of codimension one abelian subvarieties (possibly translated) in a complex abelian variety. In this paper, we study the cohomology of the complement of an abelian arrangement. For unimodular abelian…

Algebraic Geometry · Mathematics 2018-05-10 Christin Bibby

We investigate relative cohomology functors on subcategories of abelian categories via Auslander-Buchweitz approximations and the resulting strict resolutions. We verify that certain comparison maps between these functors are isomorphisms…

K-Theory and Homology · Mathematics 2007-06-27 Sean Sather-Wagstaff , Tirdad Sharif , Diana White

We study (non-abelian) extensions of a given super Lie algebra, identify a cohomological obstruction to the existence, parallel to the known one for Lie algebras. An analogy to the setting of covariant exterior derivatives, curvature, and…

Quantum Algebra · Mathematics 2007-05-23 Dmitri Alekseevsky , Peter W. Michor , Wolfgang Ruppert

We relate the old and new cohomology monoids of an arbitrary monoid $M$ with coefficients in semimodules over $M$, introduced in the author's previous papers, to monoid and group extensions. More precisely, the old and new second cohomology…

K-Theory and Homology · Mathematics 2017-03-29 Alex Patchkoria

We define $H$-Galois extensions for $k$-linear categories and a Hopf algebra $H$ and prove the existence of a Grothendieck spectral sequence for Hochschild-Mitchell cohomology, related to this situation. This spectral sequence is…

K-Theory and Homology · Mathematics 2007-05-23 Estanislao Herscovich , Andrea Solotar

We study the relation between Bourn's notion of peri-abelian category and conditions involving the coincidence of the Smith, Huq and Higgins commutators. In particular we show that a semi-abelian category is peri-abelian if and only if for…

Category Theory · Mathematics 2015-02-19 James R. A. Gray , Tim Van der Linden

We initiate a systematic study of cohomology theories for partial groups, algebraic structures introduced by Chermak that generalize groups by allowing only partially defined products. Inspired by classical group cohomology, we develop two…

Algebraic Topology · Mathematics 2025-12-08 Sandro Pfammatter

In this paper, we give a purely cohomological interpretation of the extension problem for associative algebras; that is the problem of extending an associative algebra by another associative algebra. We then give a similar interpretation of…

Rings and Algebras · Mathematics 2009-08-26 Alice Fialowski , Michael Penkava

In this paper we introduce the notions of cleft and Galois (with normal basis) extension associated to a weak Hopf quasigroup. We show that, under suitable conditions, both notions are equivalent. As a particular instance we recover the…

Quantum Algebra · Mathematics 2014-12-05 J. N. Alonso Álvarez , J. M. Fernández Vilaboa , R. González Rodríguez

We construct two-parameter analytic families of Galois cohomology classes interpolating the etale Abel--Jacobi images of generalised Heegner cycles, with both the modular form and Grossencharacter varying in p-adic families.

Number Theory · Mathematics 2021-01-27 Dimitar Jetchev , David Loeffler , Sarah Livia Zerbes
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