English

The site R^+_G for a profinite group G

Algebraic Topology 2007-05-23 v1 Category Theory

Abstract

Let G be a non-finite profinite group and let G-Sets_{df} be the canonical site of finite discrete G-sets. Then the category R^+_G, defined by Devinatz and Hopkins, is the category obtained by considering G-Sets_{df} together with the profinite G-space G itself, with morphisms being continuous G-equivariant maps. We show that R^+_G is a site when equipped with the pretopology of epimorphic covers. Also, we explain why the associated topology on R^+_G is not subcanonical, and hence, not canonical. We note that, since R^+_G is a site, there is automatically a model category structure on the category of presheaves of spectra on the site. Finally, we point out that such presheaves of spectra are a nice way of organizing the data that is obtained by taking the homotopy fixed points of a continuous G-spectrum with respect to the open subgroups of G.

Cite

@article{arxiv.math/0610772,
  title  = {The site R^+_G for a profinite group G},
  author = {Daniel G. Davis},
  journal= {arXiv preprint arXiv:math/0610772},
  year   = {2007}
}

Comments

14 pages, submitted for publication

R2 v1 2026-07-22T17:44:58.834Z