English

The stable Galois correspondence for real closed fields

Algebraic Topology 2017-02-01 v1 Algebraic Geometry

Abstract

In previous work, the authors constructed and studied a lift of the Galois correspondence to stable homotopy categories. In particular, if L/kL/k is a finite Galois extension of fields with Galois group GG, there is a functor cL/kc_{L/k}^* from the GG-equivariant stable homotopy category to the stable motivic homotopy category over kk such that cL/k(G/H+)=Spec(LH)+c_{L/k}^*(G/H_+) = Spec(L^H)_+. We proved that when kk is a real closed field and L=k[i]L=k[i], the restriction of cL/kc_{L/k}^* to the η\eta-complete subcategory is full and faithful. Here we "uncomplete" this theorem so that it applies to cL/kc_{L/k}^* itself. Our main tools are Bachmann's theorem on the (2,η)(2,\eta)-periodic stable motivic homotopy category and an isomorphism range for the map on bigraded stable stems induced by C2C_2-equivariant Betti realization.

Keywords

Cite

@article{arxiv.1701.09099,
  title  = {The stable Galois correspondence for real closed fields},
  author = {J. Heller and K. Ormsby},
  journal= {arXiv preprint arXiv:1701.09099},
  year   = {2017}
}

Comments

8 pages, comments welcome!

R2 v1 2026-06-22T18:05:26.972Z