Mathematics Preprints 2009
09.01 : BROWN, R.
`Double modules', double categories and groupoids, and a new homotopical double groupoid
Summary:We give a rather general construction of double categories and so, under further conditions, double groupoids, from a structure we call a `double module'.
We also give a homotopical construction of a double groupoid from a triad consisting of a space, two subspaces, and a set of base points, under a condition which also implies that this double groupoid contains two second relative homotopy groups.
- dbgpdnew09.pdf (latest revision: 22/03/09)