## Normal bases for Hopf-Galois algebras

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**130**(2002), 2853-2856 Request permission

## Abstract:

Let $H$ be a Hopf algebra over a commutative ring $R$ such that $H$ is a finitely generated, projective module over $R$, let $A$ be a right $H$-comodule algebra, and let $B$ be the subalgebra of $H$-coinvariant elements of $A$. If $A$ is a Galois extension of $B$ and $B$ is a local subalgebra of the center of $A$, then $A$ is a cleft right $H$-comodule algebra or, equivalently, there is a normal basis for $A$ over $B$.## References

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## Additional Information

**H. F. Kreimer**- Affiliation: Department of Mathematics, Florida State University, Tallahassee, Florida 32306-4510
- Email: kreimer@math.fsu.edu
- Received by editor(s): April 11, 2001
- Received by editor(s) in revised form: May 23, 2001
- Published electronically: March 14, 2002
- Communicated by: Martin Lorenz
- © Copyright 2002 American Mathematical Society
- Journal: Proc. Amer. Math. Soc.
**130**(2002), 2853-2856 - MSC (2000): Primary 16W30
- DOI: https://doi.org/10.1090/S0002-9939-02-06442-0
- MathSciNet review: 1908907