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arXiv · 1002.2936

Splitting in the K-theory localization sequence of number fields

Luca Caputo
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Abstract

Let p be a rational prime and let F be a number field. Then, for each i>0, there is a short exact localization sequence for K_{2i}(F). If p is odd or F is nonexceptional, we find necessary and sufficient conditions for this exact sequence to split: these conditions involve coinvariants of twisted p-parts of the p-class groups of certain subfields of the fields F(μ_{p^n}) for n\in N. We also compare our conditions with the weaker condition WK^{et}_{2i}(F)=0 and give some example.

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Luca Caputo. 2010-02-25. Splitting in the K-theory localization sequence of number fields. https://arxiv.org/abs/1002.2936

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