2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67435This is a slightly edited version of the transparencies for a seminar at UCL, May 7, 2003. It is intended to give a quick view of background, ideas, and some calculations, in the applicatioon of some non commutative methods to algebraic topology.Uses xypic, color. 25 pages in transparency format (not using slides class)Algebraic TopologyCategory Theory01-01,16E05,18D05,18D35,55P15,55Q05text