English

Semidirect product decomposition of Coxeter groups

Group Theory 2008-07-09 v3

Abstract

Let (W,S)(W,S) be a Coxeter system, let S=I˙JS=I \dot{\cup} J be a partition of SS such that no element of II is conjugate to an element of JJ, let J~\widetilde{J} be the set of WIW_I-conjugates of elements of JJ and let W~\widetilde{W} be the subgroup of WW generated by J~\widetilde{J}. We show that W=W~WIW=\widetilde{W} \rtimes W_I and that (W~,J~)(\widetilde{W},\widetilde{J}) is a Coxeter system.

Keywords

Cite

@article{arxiv.0805.4100,
  title  = {Semidirect product decomposition of Coxeter groups},
  author = {Cédric Bonnafé and Matthew J. Dyer},
  journal= {arXiv preprint arXiv:0805.4100},
  year   = {2008}
}

Comments

28 pages, one table. We have added some comments on parabolic subgroups, double cosets representatives, finite and affine Weyl groups, invariant theory, Solomon descent algebra

R2 v1 2026-06-21T10:44:30.053Z