COHOMOLOGY GROUPS OF RADICAL EXTENSIONS
نویسندگان
چکیده
منابع مشابه
Galois Groups of Radical Extensions
Theorem 1.1 (Kummer theory). Let m ∈ Z>0, and suppose that the subgroup μm(K) = {ζ ∈ K∗ : ζ = 1} of K∗ has order m. Write K∗1/m for the subgroup {x ∈ K̄∗ : x ∈ K∗} of K̄∗. Then K(K∗1/m) is the maximal abelian extension of exponent dividing m of K inside K̄, and there is an isomorphism Gal(K(K∗1/m)/K) ∼ −→ Hom(K∗, μm(K)) that sends σ to the map sending α to σ(β)/β, where β ∈ K∗1/m satisfies β = α.
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ژورنال
عنوان ژورنال: Journal of the Korean Mathematical Society
سال: 2007
ISSN: 0304-9914
DOI: 10.4134/jkms.2007.44.1.151