Symmetries in Yetter-Drinfel'd-Long categories

Dongdong Yan, Shuanhong Wang

Let $H$ be a Hopf algebra and $\mathcal{L}\mathcal{R}(H)$ the category of Yetter-Drinfel'd-Long bimodules over $H$. We first give sufficient and necessary conditions for $\mathcal{L}\mathcal{R}(H)$ to…