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Related papers: A simple characterization of Quillen adjunctions

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Originally enriched categories were defined over a monoidal category, but it was gradually realized that important examples can only be included when one enriches over more general structures such as bicategories and virtual double…

Category Theory · Mathematics 2025-07-09 Soichiro Fujii , Stephen Lack

We construct explicit models of universal $H \mathbb{Z}[J^{-1}]$-acyclic spaces $\mathcal M$, for any subset $J$ of the prime numbers. The corresponding nullification functors provide thus plus construction functors for ordinary homology…

Algebraic Topology · Mathematics 2025-12-10 Guille Carrión Santiago , Ramón Flores , Jérôme Scherer

We show that a profinite completion functor for (simplicial or topological) operads with good homotopical properties can be constructed as a left Quillen functor from an appropriate model category of infinity-operads to a certain model…

Algebraic Topology · Mathematics 2021-07-22 Thomas Blom , Ieke Moerdijk

We prove a class of equivalences of additive functor categories that are relevant to enumerative combinatorics, representation theory, and homotopy theory. Let $\mathscr{X}$ denote an additive category with finite direct sums and split…

Category Theory · Mathematics 2019-04-01 Stephen Lack , Ross Street

On the category of bisimplicial sets there are different Quillen closed model structures associated to various definitions of fibrations. In one of them, which is due to Bousfield and Kan and that consists of seeing a bisimplicial set as a…

Algebraic Topology · Mathematics 2007-06-29 Antonio Cegarra , Remedios Gomez

In the case of $(\infty,1)$-categories, the homotopy coherent nerve gives a right Quillen equivalence between the models of simplicially enriched categories and of quasi-categories. This shows that homotopy coherent diagrams of…

Algebraic Topology · Mathematics 2024-02-07 Lyne Moser , Nima Rasekh , Martina Rovelli

We construct the quadratic analogue of the boson Fock functor. While in the first order case all contractions on the 1--particle space can be second quantized, the semigroup of contractions that admit a quadratic second quantization is much…

Functional Analysis · Mathematics 2013-11-26 Luigi Accardi , Ameur Dhahri

In this work, we study the notion of cofinal functor of $\infty$-bicategories with respect to the theory of partially lax colimits. The main result of this paper is a characterization of cofinal functors of $\infty$-bicategories via…

Algebraic Topology · Mathematics 2023-04-17 Fernando Abellán , Walker H. Stern

For an adjoint pair $(F, G)$ of functors, we prove that $G$ is a separable functor if and only if the defined monad is separable and the associated comparison functor is an equivalence up to retracts. In this case, under an idempotent…

Rings and Algebras · Mathematics 2016-11-01 Xiao-Wu Chen

It is proved that the projective model structure of the category of topologically enriched diagrams of topological spaces over a topologically enriched locally contractible small category is Quillen equivalent to the standard Quillen model…

Category Theory · Mathematics 2019-12-19 Philippe Gaucher

We prove the compatibility between the suspension construction and the complicial nerve of $\omega$-categories. As a motivating application, we produce a Quillen pair between the models of $(\infty,n)$-categories given by Rezk's complete…

Algebraic Topology · Mathematics 2022-06-07 Viktoriya Ozornova , Martina Rovelli

We give an elementary construction of a certain class of model structures. In particular, we rederive the Kan model structure on simplicial sets without the use of topological spaces, minimal complexes, or any concrete model of fibrant…

Category Theory · Mathematics 2017-08-29 Christian Sattler

In this paper we call generalized lax epimorphism a functor defined on a ring with several objects, with values in an abelian AB5 category, for which the associated restriction functor is fully faithful. We characterize such a functor with…

Category Theory · Mathematics 2009-11-24 George Ciprian Modoi

It is well-known in universal algebra that adding structure and equational axioms generates forgetful functors between varieties, and such functors all have left adjoints. The category of elementary doctrines provides a natural framework…

Category Theory · Mathematics 2024-05-14 Francesca Guffanti

This paper describes several cases of adjunction in the homomorphism preorder of relational structures. We say that two functors $\Lambda$ and $\Gamma$ between thin categories of relational structures are adjoint if for all structures…

Combinatorics · Mathematics 2024-04-10 Víctor Dalmau , Andrei Krokhin , Jakub Opršal

We introduce and study relatively divisible and relatively flat objects in exact categories in the sense of Quillen. For every relative cotorsion pair $(\mathcal{A},\mathcal{B})$ in an exact category $\mathcal{C}$, $\mathcal{A}$ coincides…

Category Theory · Mathematics 2018-10-30 Septimiu Crivei , Derya Keskin Tütüncü

In a previous work, we have introduced a weakening of Quillen model categories called weak model categories. They still allow all the usual constructions of model category theory, but are easier to construct and are in some sense better…

Category Theory · Mathematics 2020-11-26 Simon Henry

Auslander-Reiten duality for module categories is generalised to Grothendieck abelian categories that have a sufficient supply of finitely presented objects. It is shown that Auslander-Reiten duality amounts to the fact that the functor…

Representation Theory · Mathematics 2016-04-12 Henning Krause

We show that the fibrant objects in the minimal model structure on the category of simplicial sets are characterized by a lifting condition with respect to maps which resemble the horn inclusions that define Kan complexes.

Category Theory · Mathematics 2023-10-12 Matthew Feller

In this paper, we investigate the properties of the category of equivariant diagram spectra indexed on the category W_G of based G-spaces homeomorphic to finite G-CW-complexes for a compact Lie group G. Using the machinery of Mandell, May,…

Algebraic Topology · Mathematics 2009-06-30 Andrew Blumberg