An action-free characterization of weak Hopf-Galois extensions
نویسنده
چکیده
We define comodule algebras and Galois extensions for actions of bialgebroids. Using just module conditions we characterize the Frobenius extensions that are Galois as depth two and right balanced extensions. As a corollary, we obtain characterizations of certain weak and ordinary Hopf-Galois extensions without reference to action in the hypothesis. 2000 AMS Subject Classification: 13B05, 16W30
منابع مشابه
Galois Theory for Bialgebroids, Depth Two and Normal Hopf Subalgebras
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