Holmstrom Kato conjectures

arXiv:0910.2803 Hasse principles for higher-dimensional fields from arXiv Front: math.AG by Uwe Jannsen For schemes X over global or local fields, or over their rings of integers, K. Kato stated several conjectures on certain complexes of Gersten-Bloch-Ogus type, generalizing the fundamental exact sequence of Brauer groups for a global field. He proved these conjectures for low dimensions. We prove Kato’s conjecture (with infinite coefficients) over number fields. In particular this gives a Hasse principle for function fields F over a number field K, involving the corresponding function fields over all completions of K. We get a conditional result over global fields K of positive characteristic, assuming resolution of singularities. This is unconditional for X of dimension at most 3, due to recent results on resolution. There are also applications to other cases considered by Kato.

arXiv:0910.2815 Kato conjecture and motivic cohomology over finite fields from arXiv Front: math.AG by Uwe Jannsen, Shuji Saito For an arithmetical scheme X, K. Kato introduced a certain complex of Gersten-Bloch-Ogus type whose component in degree a involves Galois cohomology groups of the residue fields of all the points of X of dimension a. He stated a conjecture on its homology generalizing the fundamental exact sequences for Brauer groups of global fields. We prove the conjecture over a finite field assuming resolution of singularities. Thanks to a recently established result on resolution of singularities for embedded surfaces, it implies the unconditional vanishing of the homology up to degree 4 for X projective smooth over a finite field. We give an application to finiteness questions for some motivic cohomology groups over finite fields.

nLab page on Kato conjectures

Created on June 9, 2014 at 21:16:13 by Andreas Holmström