A Note on Galois Theory for Bialgebroids
نویسنده
چکیده
In this note we reduce certain proofs in [9, 5, 6] to depth two quasibases from one side only. This minimalistic approach leads to a characterization of Galois extensions for finite projective bialgebroids without the Frobenius extension property: a proper algebra extension is a left T -Galois extension for some right finite projective left bialgebroid T over some algebra R if and only if it is of left depth two and left balanced. Exchanging left and right in this statement, we have also a characterization of right Galois extensions for left finite projective right bialgebroids. As a corollary, we obtain insights into split monic Galois mappings and endomorphism ring theorems for depth two extensions.
منابع مشابه
Galois Theory for Bialgebroids, Depth Two and Normal Hopf Subalgebras
We reduce certain proofs in [16, 11, 12] to depth two quasibases from one side only, a minimalistic approach which leads to a characterization of Galois extensions for finite projective bialgebroids without the Frobenius extension property. We prove that a proper algebra extension is a left T -Galois extension for some right finite projective left bialgebroid over some algebra R if and only if ...
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