Galois extensions for coquasi-Hopf algebras
نویسنده
چکیده
The notions of Galois and cleft extensions are generalized for coquasi-Hopf algebras. It is shown that such an extension over a coquasi-Hopf algebra is cleft if and only if it is Galois and has the normal basis property. A Schneider type theorem ([33]) is proven for coquasi-Hopf algebras with bijective antipode. As an application, we generalize Schauenburg’s bialgebroid construction for coquasi-Hopf algebras.
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