| Abstract: A central role for cohomological duality theorems over number fields is played by a theorem of Poitou, which asserts a duality between certain Tate-cohomology groups attached to a level-compact class formation. In this paper we fill a gap in the original proof of this theorem and we give applications of the duality to the cohomology of Galois groups of extensions with restricted ramification of number fields. |
Preprint
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poitou.pdf