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arXiv · 1309.1661

Adams operations and Galois structure

G. Pappas
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Abstract

We present a new method for determining the Galois module structure of the cohomology of coherent sheaves on varieties over the integers with a tame action of a finite group. This uses a novel Adams-Riemann-Roch type theorem obtained by combining the Kunneth formula with localization in equivariant K-theory and classical results about cyclotomic fields. As an application, we show two conjectures of Chinburg-Pappas-Taylor, in the case of curves.

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G. Pappas. 2015-03-30. Adams operations and Galois structure. https://doi.org/10.2140/ant.2015.9.1477

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