Journal of Pure and Applied Algebra ( IF 0.8 ) Pub Date : 2021-01-11 , DOI: 10.1016/j.jpaa.2021.106678 Johannes Berger , Azat M. Gainutdinov , Ingo Runkel
For a finite tensor category we consider four versions of the central monad, on . Two of them are Hopf monads, and for pivotal, so are the remaining two. In that case all are isomorphic as Hopf monads. We define a monadic cointegral for to be an -module morphism , where D is the distinguished invertible object of .
We relate monadic cointegrals to the categorical cointegral introduced by Shimizu (2019), and, in case is braided, to an integral for the braided Hopf algebra in studied by Lyubashenko (1995).
Our main motivation stems from the application to finite dimensional quasi-Hopf algebras H. For the category of finite-dimensional H-modules, we relate the four monadic cointegrals (two of which require H to be pivotal) to four existing notions of cointegrals for quasi-Hopf algebras: the usual left/right cointegrals of Hausser and Nill (1994), as well as so-called γ-symmetrised cointegrals in the pivotal case, for γ the modulus of H.
For (not necessarily semisimple) modular tensor categories , Lyubashenko gave actions of surface mapping class groups on certain Hom-spaces of , in particular of on . In the case of a factorisable ribbon quasi-Hopf algebra, we give a simple expression for the action of S and T which uses the monadic cointegral.
中文翻译:
Monadic共积分及其在拟霍夫代数中的应用
对于 一个有限张量类别,我们考虑中央单子的四个版本, 上 。其中有两个是霍普夫(Hopf)单子,至关重要,其余两个也是关键。在那种情况下与Hopf monads同构。我们为 成为 模态 ,其中D是的独特的可逆对象。
我们将单子共积分与清水(2019)引入的分类共积分相关联,以防万一 编织到编织Hopf代数的积分 在 Lyubashenko(1995)研究。
我们的主要动机源于对有限维拟霍夫代数H的应用。对于有限维H模的类别,我们将四个单子共积分(其中两个需要H为枢轴)与准霍夫代数的四个现存协积分概念相关:Hausser和Nill( 1994年),以及在关键情况下所谓的γ对称共积分,对于γ,H的模量。
对于(不一定是半简单的)模块化张量类别 ,柳巴申科(Lyubashenko)在 ,尤其是 上 。在可分解带状拟霍夫代数的情况下,我们给出使用单子共积分的S和T的作用的简单表达式。