English
Related papers

Related papers: Segal Group Actions

200 papers

In a previous paper we lifted Charles Rezk's complete Segal model structure on the category of simplicial spaces to a Quillen equivalent one on the category of "relative categories," and our aim in this successor paper is to obtain a more…

Algebraic Topology · Mathematics 2011-01-05 C. Barwick , D. M. Kan

We define and discuss G-formality for certain spaces endowed with an action by a compact Lie group. This concept is essentially formality of the Borel construction of the space in a category of commutative differential graded algebras over…

Algebraic Topology · Mathematics 2007-05-23 Steven Lillywhite

We study group action on bimodules and bimodule categories and prove for them analogues of the results known for representations of skew group algebras, mainly in the case, when the action is separable.

Representation Theory · Mathematics 2016-03-02 Yuriy A. Drozd

We will generalize the projective model structure in the category of unbounded complexes of modules over a commutative ring to the category of unbounded complexes of quasi-coherent sheaves over the projective line. Concretely we will define…

Algebraic Geometry · Mathematics 2014-02-26 Edgar Enochs , Sergio Estrada , J. R. Garcia-Rozas

Let X be an algebraic variety with an action of an algebraic group G. Suppose X has a full exceptional collection of sheaves, and these sheaves are invariant under the action of the group. We construct a semiorthogonal decomposition of…

Algebraic Geometry · Mathematics 2015-05-13 Alexei Elagin

Let $\bf C$ be a coreflective subcategory of a cofibrantly generated model category $\bf D$. In this paper we show that under suitable conditions $\bf C$ admits a cofibrantly generated model structure which is left Quillen adjunct to the…

Algebraic Topology · Mathematics 2013-04-15 Tadayuki Haraguchi

In this paper, which is subsequent to our previous paper [PS] (but can be read independently from it), we continue our study of the closed model structure on the category $\mathrm{Cat}_{\mathrm{dgwu}}(\Bbbk)$ of small weakly unital dg…

Category Theory · Mathematics 2020-07-28 Piergiorgio Panero , Boris Shoikhet

In this note we consider partial model categories, by which we mean relative categories that satisfy a weakened version of the model category axioms involving only the weak equivalences. More precisely, a partial model category will be a…

Algebraic Topology · Mathematics 2013-01-22 C. Barwick , D. M. Kan

We here present rudiments of an approach to geometric actions in noncommutative algebraic geometry, based on geometrically admissible actions of monoidal categories. This generalizes the usual (co)module algebras over Hopf algebras which…

Algebraic Geometry · Mathematics 2009-09-22 Zoran Škoda

For a discrete metric space (or more generally a large scale space) $X$ and an action of a group $G$ on $X$ by coarse equivalences, we define a type of coarse quotient space $X_G$, which agrees up to coarse equivalence with the orbit space…

Geometric Topology · Mathematics 2017-10-05 Logan Higginbotham , Thomas Weighill

In this paper we prove that for any simplicial set $B$, there is a Quillen equivalence between the covariant model structure on $\mathbf{S}/B$ and a certain localization of the projective model structure on the category of simplicial…

Algebraic Topology · Mathematics 2017-10-06 Danny Stevenson

We construct model structures on cyclic dendroidal sets and cyclic dendroidal spaces for cyclic quasi-operads and complete cyclic dendroidal Segal spaces, respectively. We show these models are Quillen equivalent to the model structure for…

Algebraic Topology · Mathematics 2025-07-15 Brandon Doherty , Philip Hackney

A condition of geometric modular action is proposed as a selection principle for physically interesting states on general space-times. This condition is naturally associated with transformation groups of partially ordered sets and provides…

Mathematical Physics · Physics 2007-05-23 Detlev Buchholz , Olaf Dreyer , Martin Florig , Stephen J. Summers

The Marle-Guillemin-Sternberg (MGS) form is local model for a neighborhood of an orbit of a Hamiltonian Lie group action on a symplectic manifold. One of the main features of the MGS form is that it puts simultaneously in normal form the…

Symplectic Geometry · Mathematics 2025-01-23 Miguel Rodriguez-Olmos , Miguel Teixidó-Román

We state a conjecture about the Weyl group action coming from Geometric Satake on zero-weight spaces in terms of equivariant multiplicities of Mirkovi\'c-Vilonen cycles. We prove it for small coweights in type A. In this case, using work of…

Representation Theory · Mathematics 2018-11-13 Dinakar Muthiah

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

In this paper, we construct a semigroup associated to an action of countable discrete group on a compact Hausdorff space, that can be regarded as a higher dimensional generalization of the type semigroup. Using this generalized type…

Dynamical Systems · Mathematics 2021-07-01 Xin Ma

In this paper we describe a classifying theory for families of simplicial topological groups. If $B$ is a topological space and $G$ is a simplicial topological group, then we can consider the non-abelian cohomology $H(B,G)$ of $B$ with…

Algebraic Topology · Mathematics 2016-04-29 Danny Stevenson

The purpose of this short note is to illustrate the utility of (semi-) dendroidal objects in describing certain 'up-to-homotopy' operads. Specifically, we exhibit a semi-dendroidal space satisfying the Segal condition, whose evaluation at a…

Algebraic Topology · Mathematics 2020-07-03 Philip Hackney

In this paper we establish Koszul duality between dg categories and a class of curved coalgebras, generalizing the corresponding result for dg algebras and conilpotent curved coalgebras. We show that the normalized chain complex functor…

Category Theory · Mathematics 2024-01-29 Julian Holstein , Andrey Lazarev