A finiteness theorem in the Galois cohomology of algebraic number fields

Raskind, Wayne

doi:10.1090/S0002-9947-1987-0902795-5

A finiteness theorem in the Galois cohomology of algebraic number fields

Author: Wayne Raskind
Journal: Trans. Amer. Math. Soc. 303 (1987), 743-749
MSC: Primary 11R34; Secondary 14C15, 19E08, 19E15
DOI: https://doi.org/10.1090/S0002-9947-1987-0902795-5
MathSciNet review: 902795
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Abstract: In this note we show that if is an algebraic number field with algebraic closure $\overline k$ and is a finitely generated, free ${{\mathbf{Z}}_l}$ -module with continuous $\operatorname{Gal} (\overline k /k)$ -action, then the continuous Galois cohomology group ${H^1}(k,\,M)$ is a finitely generated ${{\mathbf{Z}}_l}$ -module under certain conditions on (see Theorem 1 below). Also, we present a simpler construction of a mapping due to S. Bloch which relates torsion algebraic cycles and étale cohomology.

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