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We prove that the bar construction of an $E_\infty$ algebra forms an $E_\infty$ algebra. To be more precise, we provide the bar construction of an algebra over the surjection operad with the structure of a Hopf algebra over the…

Algebraic Topology · Mathematics 2007-05-23 Benoit Fresse

To any left system of diagram categories or to any left pointed derivateur (in the sense of Grothendieck) a K-theory space is associated. This K-theory space is shown to be canonically an infinite loop space and to have a lot of common…

K-Theory and Homology · Mathematics 2007-05-23 Grigory Garkusha

In Part 1, we describe six projective-type model structures on the category of differential graded modules over a differential graded algebra A over a commutative ring R. When R is a field, the six collapse to three and are well-known, at…

Category Theory · Mathematics 2014-12-03 Tobias Barthel , J. P. May , Emily Riehl

By using the Dold-Kan correspondence we construct a Quillen adjunction between the model categories of non-cocommutative coassociative simplicial and differential graded coalgebras over a field. We restrict to categories of connected…

Category Theory · Mathematics 2015-06-02 Hermann Soré

We make use of the cotangent complex formalism developed by Lurie to formulate Quillen cohomology of algebras over an enriched operad. Additionally, we introduce a spectral Hochschild cohomology theory for enriched operads and algebras over…

Algebraic Topology · Mathematics 2025-04-21 Truong Hoang

Starting from the observation that distinct notions of copying have arisen in different categorical fields (logic and computation, contrasted with quantum mechanics) this paper addresses the question of when, or whether, they may coincide.…

Category Theory · Mathematics 2013-05-21 Peter Hines

Curved algebras are a generalization of differential graded algebras which have found numerous applications recently. The goal of this foundational article is to introduce the notion of a curved operad, and to develop the operadic calculus…

Algebraic Topology · Mathematics 2023-12-12 Victor Roca i Lucio

Using the $E_\infty-$structure on singular cochains, we construct a homotopy coherent map from the cyclic bar construction of the differential graded algebra of cochains on a space to a model for the cochains on its free loop space. This…

Algebraic Topology · Mathematics 2017-05-04 Massimiliano Ungheretti

Let $C$ be a differential graded coalgebra, $ \bar\Omega C$ the Adams cobar construction and $C^\vee$ the dual algebra. We prove that for a large class of coalgebras $C$ there is a natural isomorphism of Gerstenhaber algebras between the…

Algebraic Topology · Mathematics 2007-05-23 Yves Félix , Luc Menichi , Jean-Claude Thomas

The Andr\'e-Quillen cohomology of an algebra with coefficients in a module is defined by deriving a functor based on K\"ahler differential forms. It can be computed using a cofibrant resolution of the algebra in a model category structure…

Algebraic Topology · Mathematics 2024-09-26 Joan Bellier-Millès , Sinan Yalin

Given a pair of number fields with isomorphic rings of adeles, we construct bijections between objects associated to the pair. For instance we construct an isomorphism of Brauer groups that commutes with restriction. We additionally…

Group Theory · Mathematics 2018-11-14 Benjamin Linowitz , D. B. McReynolds , Nicholas Miller

In this extended note we give a precise definition of fully extended topological field theories \`a la Lurie. Using complete $n$-fold Segal spaces as a model, we construct an $(\infty,n)$-category of $n$-dimensional cobordisms, possibly…

Algebraic Topology · Mathematics 2019-03-20 Damien Calaque , Claudia Scheimbauer

It is shown that any Lie affgebra, that is an algebraic system consisting of an affine space together with a bi-affine bracket satisfying affine versions of the antisymmetry and Jacobi identity, is isomorphic to a Lie algebra together with…

Rings and Algebras · Mathematics 2024-09-04 Ryszard R. Andruszkiewicz , Tomasz Brzeziński , Krzysztof Radziszewski

This article presents a natural extension of the tensor algebra. In addition to "left multiplications" by vectors, we can consider "derivations" by covectors as basic operators on this extended algebra. These two types of operators satisfy…

Representation Theory · Mathematics 2011-05-23 Minoru Itoh

In this article, we give Maurer-Cartan characterizations of equivariant Lie superalgebra structures. We introduce equivariant cohomology and equivariant formal deformation theory of Lie superalgebras. As an application of equivariant…

General Mathematics · Mathematics 2023-01-04 RB Yadav , Subir Mukhopadhyay

The main result of this work is a new proof and generalization of Lazard's comparison theorem of locally analytic group cohomology with Lie algebra cohomology for K-Lie groups, where K is a finite extension of the p-adic numbers. We show…

Rings and Algebras · Mathematics 2012-01-24 Sabine Lechner

Using the theory of extensions of L-infinity algebras, we construct rational homotopy models for classifying spaces of fibrations, giving answers in terms of classical homological functors, namely the Chevalley-Eilenberg and Harrison…

Algebraic Topology · Mathematics 2013-12-13 Andrey Lazarev

An affine Lie algebra acts on cohomology groups of quiver varieties of affine type. A Heisenberg algebra acts on cohomology groups of Hilbert schemes of points on a minimal resolution of a Kleinian singularity. We show that in the case of…

Representation Theory · Mathematics 2010-02-26 Kentaro Nagao

Curved algebras are algebras endowed with a predifferential, which is an endomorphism of degree -1 whose square is not necessarily 0. This makes the usual definition of quasi-isomorphism meaningless and therefore the homotopical study of…

Algebraic Topology · Mathematics 2025-06-24 Joan Bellier-Millès , Gabriel C. Drummond-Cole

This is a companion paper our previous submission "\infty-categories monoidales rigides et caracteres de Chern", in which we give a comparison between functions on the derived loop space of a smooth scheme of caracteristic zero, and its…

Algebraic Geometry · Mathematics 2009-04-22 B. Toen , G. Vezzosi