Building the bicategory Span
arXiv:1501.00792
Abstract
Given any category with pullbacks and a terminal object, we show that the data consisting of the objects of , the spans of , and the isomorphism classes of spans of spans of , forms a bicategory. We denote this bicategory Span and show that this construction can be applied to give a bicategory of -manifolds, cobordisms of those manifolds, and cobordisms of cobordisms.
34 pages