English

Strong fusion control and stable equivalences

Representation Theory 2013-09-20 v2

Abstract

This article is dedicated to the proof of the following theorem. Let G be a finite group, p be a prime number, and e be a p-block of G. Assume that the centraliser C_G(P) of an e-subpair (P,e_P) "strongly" controls the fusion of the block e, and that a defect group of e is either abelian or (for odd p) has a non-cyclic center. Then there exists a stable equivalence of Morita type between the block algebras OGe and OC_G(P)e_P, where O is a complete discrete valuation ring of residual characteristic p. This stable equivalence is constructed by gluing together a family of local Morita equivalences, which are induced by bimodules with fusion-stable endo-permutation sources. Brou\'e had previously obtained a similar result for principal blocks, in relation with the search for a modular proof of the odd Z*p-theorem. Thus our theorem points towards a block-theoretic analogue of the Z*p-theorem, which we state in terms of fusion control and Morita equivalences.

Keywords

Cite

@article{arxiv.1308.5477,
  title  = {Strong fusion control and stable equivalences},
  author = {Erwan Biland},
  journal= {arXiv preprint arXiv:1308.5477},
  year   = {2013}
}

Comments

Revised version (new abstract and introduction), 22 pages. Comments are most welcome

R2 v1 2026-06-22T01:14:47.089Z