English

Dualizing spheres for compact $p$-adic analytic groups and duality in chromatic homotopy

Algebraic Topology 2022-05-18 v2

Abstract

The primary goal of this paper is to study Spanier-Whitehead duality in the K(n)K(n)-local category. One of the key players in the K(n)K(n)-local category is the Lubin-Tate spectrum EnE_n, whose homotopy groups classify deformations of a formal group law of height nn, in the implicit characteristic pp. It is known that EnE_n is self-dual up to a shift; however, that does not fully take into account the action of the Morava stabilizer group Gn\mathbb{G}_n, or even its subgroup of automorphisms of the formal group in question. In this paper we find that the Gn\mathbb{G}_n-equivariant dual of EnE_n is in fact EnE_n twisted by a sphere with a non-trivial (when n>1n>1) action by Gn\mathbb{G}_n. This sphere is a dualizing module for the group Gn\mathbb{G}_n, and we construct and study such an object IGI_{\mathcal{G}} for any compact pp-adic analytic group G\mathcal{G}. If we restrict the action of G\mathcal{G} on IGI_{\mathcal{G}} to certain type of small subgroups, we identify IGI_{\mathcal{G}} with a specific representation sphere coming from the Lie algebra of G\mathcal{G}. This is done by a classification of pp-complete sphere spectra with an action by an elementary abelian pp-group in terms of characteristic classes, and then a specific comparison of the characteristic classes in question. The setup makes the theory quite accessible for computations, as we demonstrate in the later sections of this paper, determining the K(n)K(n)-local Spanier-Whitehead duals of EnhHE_n^{hH} for select choices of pp and nn and finite subgroups HH of Gn\mathbb{G}_n.

Keywords

Cite

@article{arxiv.2010.09518,
  title  = {Dualizing spheres for compact $p$-adic analytic groups and duality in chromatic homotopy},
  author = {Agnès Beaudry and Paul G. Goerss and Michael J. Hopkins and Vesna Stojanoska},
  journal= {arXiv preprint arXiv:2010.09518},
  year   = {2022}
}

Comments

Final version, accepted for publication in Invent. Math. Comments always welcome!