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arXiv · 1004.5235

Hopf-Galois extensions and isomorphisms of small categories

S. Caenepeel
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Abstract

We associate two linear categories with two objects to a module over the subalgebra of coinvariants of a Hopf-Galois extension, and prove that they are isomorphic. The structure Theorem for cleft extensions, and the Militaru \cStefan lifting Theorem can be obtained using these isomorphisms.

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S. Caenepeel. 2010-04-29. Hopf-Galois extensions and isomorphisms of small categories. https://arxiv.org/abs/1004.5235

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