Characteristic 0 and p analogies, and some motivic cohomology

Manuel Blickle; Hélène Esnault; Kay Rülling

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Characteristic 0 and p analogies, and some motivic cohomology

Manuel Blickle·Hélène Esnault·Kay Rülling

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Abstract

The purpose of this survey is to explain some recent results about analogies between characteristic 0 and characteristic $p>0$ geometry, and to discuss an infinitesimal variant of motivic cohomology. More specifically, we review results showing that the big de Rham Witt complex of a field is a complex of 0-cycles (section 2), as well as results showing analogies between char. $p>0$ and char. 0 geometry. Some of those results determine local cohomology invariants of singular varieties (section 3) and others are concerned with congruences modulo $q$-powers for the number of rational points of varieties defined over $\F_q$ (section 1).

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Manuel Blickle, Hélène Esnault, Kay Rülling. 2005-12-09. Characteristic 0 and p analogies, and some motivic cohomology. https://arxiv.org/abs/math/0512190

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