A Maschke type theorem for weak group entwined modules and applications.
Let \(\pi\) be a group, \(\alpha\in\pi\), and let \((A,C)_{\pi-\psi}\) be a weak \(\pi\)-entwining structure. If \(U^{\pi -C}_A(\psi)\) is the category of right \((A,C)_{\pi-\psi}\)-modules, let \(F^{(\alpha)}\colon U^{\pi-C}_A(\psi)\to M_{A_\alpha}\) be the forgetful functor to the category of right \(A_\alpha\)-modules. The authors discuss when is \(F^{(\alpha)}\) a separable functor, and apply the result to weak Doi-Hopf \(\pi\)-modules and to weak entwining modules.
scientific article; zbMATH DE number 6379542
scientific article