Submission: 2007, Sep 29
Let $k$ be a field of characteristic $\not=2$, and let $G$ be a finite group. The aim of this paper is to give a cohomological criterion for the isomorphism of multiples of trace forms of G--Galois algebras over $k$. The proof uses results concerning multiples of hermitian forms over division algebras with involution that are of independent interest.
2000 Mathematics Subject Classification: 11E72
Keywords and Phrases: G-forms, hermitian forms, Galois cohomology of linear algebraic groups, self-dual normal bases
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