English

$\mathrm{H}^4(\mathrm{Co}_0;\mathbf{Z}) = \mathbf{Z}/24$

Group Theory 2019-11-05 v3

Abstract

We show that the fourth integral cohomology of Conway's group Co0\mathrm{Co}_0 is a cyclic group of order 2424, generated by the first fractional Pontryagin class of the 2424-dimensional representation.

Cite

@article{arxiv.1707.07587,
  title  = {$\mathrm{H}^4(\mathrm{Co}_0;\mathbf{Z}) = \mathbf{Z}/24$},
  author = {Theo Johnson-Freyd and David Treumann},
  journal= {arXiv preprint arXiv:1707.07587},
  year   = {2019}
}

Comments

24 pages, 1 large table, Int. Math. Res. Not. IMRN 2018

R2 v1 2026-06-22T20:55:46.783Z