Cohomological Invariants for G - Galois Algebras and Self - Dual Normal Bases
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چکیده
We define degree two cohomological invariants for GGalois 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 ≤ 2) we show that these conditions are also sufficient.
منابع مشابه
BANFF WORKSHOP ON “DIOPHANTINE METHODS, LATTICES, AND ARITHMETIC THEORY OF QUADRATIC FORMS”: TITLES AND ABSTRACTS 1. Hour-long talks
Eva Bayer-Fluckiger (École Polytechnique Fédérale de Lausanne) Title: Galois algebras, Hasse principle and induction-restriction methods Abstract: The aim of this talk is to survey old and new results on self-dual normal bases and more generally invariants of Galois algebras. Particular attention will be given to local-global principles. Some of the results make use of an inductionrestriction m...
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تاریخ انتشار 2017