Cohomological Invariants for -Galois Algebras and Self-Dual Normal Bases
E. Bayer-Fluckiger
Ecole Polytechnique Federale de Lausanne, EPFL/FSB/MATHGEOM/CSAG Station 8, 1015 Lausanne, SwitzerlandR. Parimala
Department of Mathematics and Computer Science, Emory University Atlanta, GA 30322, USA
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Abstract
We define degree two cohomological invariants for -Galois algebras over fields of characteristic not 2, and use them to give necessary conditions for the existence of a self-dual normal basis. In some cases (for instance, when the field has cohomological dimension ) we show that these conditions are also sufficient.
Cite this article
E. Bayer-Fluckiger, R. Parimala, Cohomological Invariants for -Galois Algebras and Self-Dual Normal Bases. Doc. Math. 22 (2017), pp. 1–24
DOI 10.4171/DM/557