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arXiv · 1309.6045

Galois descent for completed Algebraic K-theory

Gunnar Carlsson·Roy Joshua
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Abstract

In this paper we consider the problem of Galois descent for suitably completed algebraic K-theory of fields. One of the main results is a suitable form of rigidity for Borel-style generalized equivariant cohomology with respect to certain spectra. In order to apply this to the problem at hand, we need to invoke a derived Atiyah-Segal completion theorem for pro-groups. In the present paper, the authors apply such a derived completion theorem proven by the first author elsewhere. These two results provide a proof of the Galois descent problem for equivariant algebraic K-theory as formulated by the first author, at least when restricted to the case where the absolute Galois groups are pro-$l$ groups for some prime $l$ different from the characteristic of the base field and the K-theory spectrum is completed at the same prime $l$. Work in progress hopes to remove these restrictions.

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Gunnar Carlsson, Roy Joshua. 2013-09-26. Galois descent for completed Algebraic K-theory. https://arxiv.org/abs/1309.6045

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