English

Bounding the $K(p-1)$-local exotic Picard group at $p>3$

Algebraic Topology 2024-07-03 v2

Abstract

In this paper, we bound the descent filtration of the exotic Picard group κn\kappa_n, for a prime number p>3 and n=p-1. Our method involves a detailed comparison of the Picard spectral sequence, the homotopy fixed point spectral sequence, and an auxiliary β\beta-inverted homotopy fixed point spectral sequence whose input is the Farrell-Tate cohomology of the Morava stabilizer group. Along the way, we deduce that the K(n)-local Adams-Novikov spectral sequence for the sphere has a horizontal vanishing line at 3n2+13n^2+1 on the E2n2+2E_{2n^2+2}-page. The same analysis also allows us to express the exotic Picard group of K(n)K(n)-local modules over the homotopy fixed points spectrum EnhN\mathrm{E}_n^{hN}, where N is the normalizer in Gn\mathbb{G}_n of a finite cyclic subgroup of order p, as a subquotient of a single continuous cohomology group H2n+1(N,π2nEn)H^{2n+1}(N,\pi_{2n}\mathrm{E}_n).

Keywords

Cite

@article{arxiv.2403.15572,
  title  = {Bounding the $K(p-1)$-local exotic Picard group at $p>3$},
  author = {Irina Bobkova and Andrea Lachmann and Ang Li and Alicia Lima and Vesna Stojanoska and Adela YiYu Zhang},
  journal= {arXiv preprint arXiv:2403.15572},
  year   = {2024}
}