Paths and cylinders
The category of augmented simplicial sets is the category of presheaves on the augmented version of the simplex category :
This is the category whose objects are augmented simplicial sets and whose morphisms are the evident morphisms between these.
The join of simplicial sets is most naturally defined via a construction on augmented simplicial sets.
Revised on November 4, 2010 08:48:44
by Urs Schreiber