English
Related papers

Related papers: Biset functors as module Mackey functors, and its …

200 papers

In this article, we consider a formulation of biset functors using the 2-category of finite sets with variable finite group actions. We introduce a 2-category $\mathbb{S}$, on which a biset functor can be regarded as a special kind of…

Category Theory · Mathematics 2015-12-08 Hiroyuki Nakaoka

For any finite group G, we define a bivariant functor from the Dress category of finite G-sets to the conjugation biset category, whose objects are subgroups of G, and whose morphisms are generated by certain bifree bisets. Any additive…

Group Theory · Mathematics 2013-01-31 I. Hambleton , L. R. Taylor , E. B. Williams

We introduce the theory of biset functors defined on finite categories. Previously, biset functors have been defined on groups, and in that context they are closely related to Mackey functors. Standard examples on groups include…

Representation Theory · Mathematics 2023-07-18 Peter Webb

We compare the bicategory of spans with that of bisets (a.k.a. bimodules, distributors, profunctors) in the context of finite groupoids. We construct in particular a well-behaved pseudo-functor from spans to bisets. This yields an…

Category Theory · Mathematics 2020-09-10 Ivo Dell'Ambrogio , James Huglo

Let $G$ be a finite group. In [HTW], Hambleton, Taylor and Williams have considered the question of comparing Mackey functors for $G$ and biset functors defined on subgroups of $G$ and bifree bisets as morphisms. This paper proposes a…

Group Theory · Mathematics 2013-03-28 Serge Bouc

In this paper, we describe the induction functor from the category of native Mackey functors to the category of biset functors for a finite group $G$ over an algebraically closed field $k$ of characteristic zero. We prove two applications…

Group Theory · Mathematics 2014-08-13 Olcay Coşkun

Let $R$ be a commutative unital ring. We construct a category $\mathcal{C}_R$ of fractions $X/G$, where $G$ is a finite group and $X$ is a finite $G$-set, and with morphisms given by $R$-linear combinations of spans of bisets. This category…

Category Theory · Mathematics 2019-10-02 Jesús Ibarra , Alberto G. Raggi-Cárdenas , Nadia Romero

Bisets can be considered as categories. This note uses this point of view to give a simple proof of a Mackey-like formula expressing the tensor product of two induced bimodules.

Group Theory · Mathematics 2009-03-03 Serge Bouc

We classify simple modules over the Green biset functor of section Burnside rings.

Representation Theory · Mathematics 2021-04-19 Olcay Coşkun , Ruslan Muslumov

In the previous article 'A Mackey-functor theoretic interpretation of biset functors', we have constructed the 2-category $\mathbb{S}$ of finite sets with variable finite group actions, in which bicoproducts and bipullbacks exist. As shown…

Category Theory · Mathematics 2015-12-08 Hiroyuki Nakaoka

We develop and extend the theory of Mackey functors as an application of enriched category theory. We define Mackey functors on a lextensive category $\E$ and investigate the properties of the category of Mackey functors on $\E$. We show…

Category Theory · Mathematics 2007-06-21 Ross Street , Elango Panchadcharam

We study a 2-functor that assigns to a bimodule category over a finite k-linear tensor category a k-linear abelian category. This 2-functor can be regarded as a category-valued trace for 1-morphisms in the tricategory of finite tensor…

Category Theory · Mathematics 2016-01-20 Jurgen Fuchs , Gregor Schaumann , Christoph Schweigert

We study collections of additive categories $\mathcal{M}(G)$, indexed by finite groups $G$ and related by induction and restriction in a way that categorifies usual Mackey functors. We call them `Mackey 2-functors'. We provide a large…

Representation Theory · Mathematics 2020-09-16 Paul Balmer , Ivo Dell'Ambrogio

We study the classification of submodules of module categories over monoidal categories, extending ideas of Coulembier on the classification of tensor ideals in monoidal categories. We develop a framework that applies to module categories…

Representation Theory · Mathematics 2026-03-20 Hadi Salmasian , Alistair Savage , Yaolong Shen

Let $G$ be a finite group. In this paper, we first introduce a new notion, so-called the Mackey double category of $G$. Then we prove that the category of Mackey double categories and the category of Mackey functors of $G$ are equivalent.

Group Theory · Mathematics 2026-03-18 Mawei Wu

We characterize cofibrant objects in the category of functors indexed in a filtered poset and we show that these objects are acyclic. As a consequence, we show that Mackey functors over posets are also acyclic, where we define this type of…

Algebraic Topology · Mathematics 2024-07-16 Guille Carrión Santiago , Antonio Díaz Ramos

We describe the structure of bimodules (over finite dimensional algebras) which have the property that the functor of tensoring with such a bimodule sends any module to a projective module. The main result is that all such bimodules are…

Representation Theory · Mathematics 2019-06-24 Volodymyr Mazorchuk , Vanessa Miemietz , Xiaoting Zhang

The bicategorical point of view provides a natural setting for many concepts in the representation theory of monoidal categories. We show that centers of twisted bimodule categories correspond to categories of 2-dimensional natural…

Category Theory · Mathematics 2023-06-09 Bojana Femić , Sebastian Halbig

We show that the bicategory of finite groupoids and right-free permutation bimodules is a quotient of the bicategory of Mackey 2-motives introduced in arXiv:1808.04902, obtained by modding out the so-called cohomological relations. This…

Category Theory · Mathematics 2024-09-10 Paul Balmer , Ivo Dell'Ambrogio

For a non-vanishing group, we show that the evaluation functor induces an equivalence between the category of modules over the double Burnside algebra and a certain category of biset functors. Using this equivalence, we deduce that over a…

Representation Theory · Mathematics 2018-07-24 Baptiste Rognerud
‹ Prev 1 2 3 10 Next ›