English

Propagating sharp group homology decompositions

Algebraic Topology 2007-05-23 v2 Group Theory

Abstract

A collection C of subgroups of a finite group G can give rise to three different standard formulas for the cohomology of G in terms of either: the subgroups in C; or their centralizers; or their normalizers. We give a short but systematic study of the relationship among such formulas for nine standard collections C of p-subgroups, obtaining some new formulas in the process. To do this, we exhibit some sufficient conditions on the poset C which imply comparison results.

Keywords

Cite

@article{arxiv.math/0402270,
  title  = {Propagating sharp group homology decompositions},
  author = {Jesper Grodal and Stephen D. Smith},
  journal= {arXiv preprint arXiv:math/0402270},
  year   = {2007}
}

Comments

12 pages. Extra counterexamples added. To appear in Advances in Math