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In this paper, we introduce a new category of simplicial effects that extends the categories of effect algebras and their multi-object counterpart, effect algebroids. Our approach is based on relaxing the associativity condition satisfied…

Category Theory · Mathematics 2025-02-11 Cihan Okay , Victor Castillo , Walker H. Stern

We study the simplicial coalgebra of chains on a simplicial set with respect to three notions of weak equivalence. To this end, we construct three model structures on the category of reduced simplicial sets for any commutative ring R. The…

Algebraic Topology · Mathematics 2024-02-06 George Raptis , Manuel Rivera

Let k be a commutative ring with unit. We endow the categories of filtered complexes and of bicomplexes of k-modules, with cofibrantly generated model structures, where the class of weak equivalences is given by those morphisms inducing a…

Algebraic Topology · Mathematics 2020-12-09 Joana Cirici , Daniela Egas Santander , Muriel Livernet , Sarah Whitehouse

We show that the category of algebraically cofibrant objects in a combinatorial and simplicial model category A has a model structure that is left-induced from that on A. In particular it follows that any presentable model category is…

Algebraic Topology · Mathematics 2014-09-09 Michael Ching , Emily Riehl

In previous work, we showed that there are appropriate model category structures on the category of simplicial categories and on the category of Segal precategories, and that they are Quillen equivalent to one another and to Rezk's complete…

Algebraic Topology · Mathematics 2013-01-04 Julia E. Bergner

By careful analysis of the comparison map from a simplicial set to its image under Kan's ex-infinity functor we obtain a new and combinatorial proof that it is a weak homotopy equivalence. Moreover, we obtain a presentation of it as a…

Category Theory · Mathematics 2020-02-14 Sean Moss

A simplicial set is said to be non-singular if the representing map of each non-degenerate simplex is degreewise injective. The inclusion into the category of simplicial sets, of the full subcategory whose objects are the non-singular…

Algebraic Topology · Mathematics 2020-01-17 Vegard Fjellbo

We construct a model structure on the category of ordered simplicial complexes, Quillen equivalent to the standard model structure on simplicial sets. This shows that simplicial complexes, which are fully combinatorial in nature, provide a…

Algebraic Topology · Mathematics 2026-05-18 Melissa Wei

We consider semisimple super Tannakian categories generated by an object whose symmetric or alternating tensor square is simple up to trivial summands. Using representation theory, we provide a criterion to identify the corresponding…

Representation Theory · Mathematics 2015-10-01 Thomas Krämer , Rainer Weissauer

Categorical structures and their pseudomaps rarely form locally presentable 2-categories in the sense of Cat-enriched category theory. However, we show that if the categorical structure in question is sufficiently weak (such as the…

Category Theory · Mathematics 2022-01-31 John Bourke

We present a family of model structures on the category of multicomplexes. There is a cofibrantly generated model structure in which the weak equivalences are the morphisms inducing an isomorphism at a fixed stage of an associated spectral…

Algebraic Topology · Mathematics 2021-01-13 Xin Fu , Ai Guan , Muriel Livernet , Sarah Whitehouse

To a bicomplex one can associate two natural filtrations, the column and row filtrations, and then two associated spectral sequences. This can be generalized to $N$-multicomplexes. We present a family of model category structures on the…

Algebraic Topology · Mathematics 2025-11-11 Joana Cirici , Muriel Livernet , Sarah Whitehouse

There are infinitely many variants of the notion of Kan fibration that, together with suitable choices of cofibrations and the usual notion of weak equivalence of simplicial sets, satisfy Quillen's axioms for a homotopy model category. The…

Category Theory · Mathematics 2008-10-29 Tibor Beke

We establish a Dwyer-Kan equivalence of relative categories of combinatorial model categories, presentable quasicategories, and other models for locally presentable (infinity,1)-categories. This implies that the underlying quasicategories…

Algebraic Topology · Mathematics 2025-02-12 Dmitri Pavlov

A characterization of simplicial objects in categories with finite products obtained by the reduced bar construction is given. The condition that characterizes such simplicial objects is a strictification of Segal's condition guaranteeing…

Category Theory · Mathematics 2015-05-20 Zoran Petric

For every functor $\mathcal{F} : \mathcal{K} \to \mathbf{C}$, where $\mathcal{K}$ is a small category and $\mathbf{C}$ is a model category which satisfies some mild hypotheses, we define a model category $\mathbf{C}^m$ of…

Category Theory · Mathematics 2016-10-27 Valery Isaev

We show that any closed model category of simplicial algebras over an algebraic theory is Quillen equivalent to a proper closed model category. By ``simplicial algebra'' we mean any category of algebras over a simplicial algebraic theory,…

Algebraic Topology · Mathematics 2008-12-05 Charles Rezk

Both simplicial sets and simplicial spaces are used pervasively in homotopy theory as presentations of spaces, where in both cases we extract the "underlying space" by taking geometric realization. We have a good handle on the category of…

Algebraic Topology · Mathematics 2015-10-20 Aaron Mazel-Gee

We construct a model structure on the category of cubical sets with connections whose cofibrations are the monomorphisms and whose fibrant objects are defined by the right lifting property with respect to inner open boxes, the cubical…

Algebraic Topology · Mathematics 2022-02-08 Brandon Doherty , Chris Kapulkin , Zachery Lindsey , Christian Sattler

We consider simplicial sets equipped with a notion of smallness, and observe that this slight "topological" extension of the "algebraic" simplicial language allows a concise reformulation of a number of classical notions in topology, e.g.…

Category Theory · Mathematics 2019-12-30 M. Gavrilovich