Partial Hopf actions on generalized matrix algebras (2412.09552v2)

Abstract: Let $\Bbbk$ be a field, $H$ a Hopf algebra over $\Bbbk$, and $R = (iM_j){1 \leq i,j \leq n}$ a generalized matrix algebra. In this work, we establish necessary and sufficient conditions for $H$ to act partially on $R$. To achieve this, we introduce the concept of an opposite covariant pair and demonstrate that it satisfies a universal property. In the special case where $H = \Bbbk G$ is the group algebra of a group $G$, we recover the conditions given in \cite{BP} for the existence of a unital partial action of $G$ on $R$.