Inner gradings and Galois extensions with normal basis

Beattie, Margaret

doi:10.1090/S0002-9939-1989-0975632-8

Inner gradings and Galois extensions with normal basis
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by Margaret Beattie PDF

Proc. Amer. Math. Soc. 107 (1989), 881-886 Request permission

Abstract:

We prove that for $G$ a finite group, a $G$-graded Azumaya algebra over a commutative ring has inner grading if and only if an associated Galois extension has normal basis.

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