Hopf-Galois module structure of tame biquadratic extensions
نویسندگان
چکیده
منابع مشابه
On the Relative Galois Module Structure of Rings of Integers in Tame Extensions
Let F be a number field with ring of integers OF and let G be a finite group. We describe an approach to the study of the set of realisable classes in the locally free class group Cl(OF G) of OF G that involves applying the work of the second-named author in the context of relative algebraic K theory. For a large class of soluble groups G, including all groups of odd order, we show (subject to ...
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is an isomorphism, which can be interpreted as the correct algebraic formulation of the condition that the G-action of X should be free, and transitive on the fibers of the map X → Y . In many applications surjectivity of the Galois map β, which, in the commutative case, means freeness of the action of G, is obvious, or at least easy to prove (it is sufficient to find 1 ⊗ h in the image for eac...
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ژورنال
عنوان ژورنال: Journal de Théorie des Nombres de Bordeaux
سال: 2012
ISSN: 1246-7405
DOI: 10.5802/jtnb.792