2 papers
math.AT2004
A homotopy double groupoid of a Hausdorff space II: a van Kampen theorem
R. Brown, H. K. Kamps, T. Porter
This paper is the second in a series exploring the properties of a functor which assigns a homotopy double groupoid with connections to a Hausdorff space. We show that this functor…
math.CT1999
Joins for (Augmented) Simplicial Sets
P. J. Ehlers, T. Porter
We introduce a notion of join for (augmented) simplicial sets generalising the classical join of geometric simplicial complexes. The definition comes naturally from the ordinal sum…