Dear Pierre, dear John, John H Palmieri schrieb: > On Jan 19, 6:28�am, Pierre <pierre.guil...@gmail.com> wrote: > I think Simon King does some group cohomology computations with Sage, > but I don't know exactly how he does it.
Indeed. One of my plans is to enrich my results by Steenrod actions, and to provide the cohomology rings in a Sage readable data base. My approach for computing cohomology rings of p-groups is: - use David Green's approach to compute minimal projective resolutions - I wrote various Cython modules for Sage that compute the visible ring structure degree by degree - Use an improved version of Dave Benson's completeness criterion. Our results: - We can compute the cohomology of all groups of order 64 in a total of less than 30 CPU-minutes. - We computed the cohomology for all groups of order 128 - We computed all but 7 cohomology rings for 3-, 5- and 7-groups up to order 625 - We computed the cohomology for the Sylow-2-subgroup of the Higman- Sims group (verifying Carlson's computation) - We were the first to compute the cohomology of the Sylow-2-subgroup of the third Conway group Our results are available at http://users.minet.uni-jena.de/~king/cohomology/ We plan to make a Sage package out of our programs. And, Pierre, by the way, I did my PhD in Strasbourg at IRMA (my advisor was Vladimir Turaev). Cheers, Simon --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
