Cech cohomology and the Capitulation kernel
arXiv:1802.06429
Abstract
We discuss the capitulation kernel associated to a degree n covering using Cech cohomology and the Kummer sequence. The main result is a five-term exact sequence that relates the capitulation kernel to the Cech cohomology of the n-th roots of unity and a certain subquotient of the group of units modulo n-th powers.
17 pages