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Related papers: Comonadic approach to pretorsion theories

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This paper studies the homotopy theory of the Grothendieck construction using model categories and semi-model categories, provides a unifying framework for the homotopy theory of operads and their algebras and modules, and uses this…

Algebraic Topology · Mathematics 2026-05-20 Michael Batanin , Florian De Leger , David White

We develop a theory of right group-like projections in Hopf algebras linking them with the theory of left coideal subalgebras with two sided counital integrals. Every right group-like projection is associated with a left coideal subalgebra,…

Quantum Algebra · Mathematics 2019-04-05 Alexandru Chirvasitu , Pawel Kasprzak , Piotr Szulim

We expand our previously founded basic theory of equiresidual algebraic geometry over an arbitrary commutative field, to a well-behaved theory of (equiresidual) algebraic varieties over a commutative field, thanks to the generalisation of…

Algebraic Geometry · Mathematics 2020-03-17 Jean Barbet-Berthet

In this article, we study monomial curves, toric ideals and monomial algebras associated to $4$-generated pseudo symmetric numerical semigroups. Namely, we determine indispensable binomials of these toric ideals, give a characterization for…

Commutative Algebra · Mathematics 2018-10-03 Mesut Şahin , Nil Şahin

We introduce rigid algebras, a generalization of rigid categories to arbitrary symmetric monoidal $(\infty,2)$-categories. We develop their general theory, showing in particular that the a priori $(\infty,2)$-category of rigid algebras is…

Category Theory · Mathematics 2026-05-25 Leor Neuhauser

We present the concept of cotorsion pairs cut along subcategories of an abelian category. This provides a generalization of complete cotorsion pairs, and represents a general framework to find approximations restricted to certain…

Category Theory · Mathematics 2022-08-02 Mindy Huerta , Octavio Mendoza , Marco A. Pérez

It is proved that classifiable simple separable nuclear purely infinite C*-algebras having finitely generated K-theory and torsion-free K_1 are semiprojective. This is accomplished by exhibiting these algebras as C*-algebras of infinite…

Operator Algebras · Mathematics 2007-05-23 Jack Spielberg

In this paper we develop the theory of operads, algebras and modules in cofibrantly generated symmetric monoidal model categories. We give J-semi model strucures, which are a slightly weaker version of model structures, for operads and…

Algebraic Topology · Mathematics 2007-05-23 Markus Spitzweck

Recent algorithmic advances in algebraic automata theory drew attention to semigroupoids (semicategories). These are mathematical descriptions of typed computational processes, but they have not been studied systematically in the context of…

Formal Languages and Automata Theory · Computer Science 2025-09-30 Attila Egri-Nagy , Chrystopher L. Nehaniv

We introduce the category of bicomodules for a comonad in a Grothendieck category whose underlying functor is right exact and preserves direct sums. We characterize comonads with a separable forgetful functor by means of cohomology groups…

Rings and Algebras · Mathematics 2007-05-23 L. El Kaoutit , J. Vercruysse

We study the cohomology of Lie superalgebras for the full complex of forms: superforms, pseudoforms and integral forms. We use the technique of spectral sequences to abstractly compute the Chevalley-Eilenberg cohomology. We first focus on…

High Energy Physics - Theory · Physics 2021-06-25 C. A. Cremonini , P. A. Grassi

A classical result of topos theory holds that the category of coalgebras for a Cartesian comonad on a topos is again a topos (Kock and Wraith, 1971). It is natural to refine this result to a topos-theoretic setting that includes universes.…

Category Theory · Mathematics 2024-05-02 Colin Zwanziger

We give a gentle introduction to the concept of folding. That is, we provide an elementary discussion of equivariant categories, their weighted Grothendieck groups, and the technical aspects of computing with them. We then perform the…

Representation Theory · Mathematics 2016-04-05 Ben Elias

For any k-coalgebra C it is shown that similar quasi-finite C-comodules have strongly equivalent coendomorphism coalgebras; (the converse is in general not true). As an application we give a general result about codepth two coalgebra…

Rings and Algebras · Mathematics 2008-08-18 F. Castano Iglesias , Lars Kadison

We prove a number of results concerning monomorphisms, epimorphisms, dominions and codominions in categories of coalgebras. Examples include: (a) representation-theoretic characterizations of monomorphisms in all of these categories that…

Quantum Algebra · Mathematics 2023-02-28 Alexandru Chirvasitu

We study monoidal 2-categories and bicategories in terms of categorical extensions and the cohomological data they determine in appropriate cohomology theories with coefficients in Picard groupoids. In particular, we analyze the hierarchy…

Category Theory · Mathematics 2024-11-19 Ettore Aldrovandi , Milind Gunjal

We introduce the notion of pre-weight structure on a triangulated category and study the corresponding pseudo-identities. We propose the notion of canonical derived equivalence between algebras that are not necessarily flat, which is…

Representation Theory · Mathematics 2025-11-20 Xiao-Wu Chen

We investigate models of algebraic theories in the category of cocommutative coalgebras over a field. We establish some of their categorical properties, similar to those of algebraic varieties. We introduce a class of categories of…

Category Theory · Mathematics 2025-11-12 Maria Bevilacqua

We prove that the homotopy theory of cofibration categories is equivalent to the homotopy theory of cocomplete quasicategories. This is achieved by presenting both homotopy theories as fibration categories and constructing an explicit…

Algebraic Topology · Mathematics 2014-11-04 Karol Szumiło

We introduce and study several new topological operads that should be regarded as nonsymmetric analogues of the operads of little 2-disks, framed little 2-disks, and Deligne-Mumford compactifications of moduli spaces of genus zero curves…

Algebraic Geometry · Mathematics 2019-05-16 Vladimir Dotsenko , Sergey Shadrin , Bruno Vallette