2015/01/05 by Franciscus Rebro, Rebro, Franciscus
Mathematics · #Algebraic structures and combinatorial models #Category Theory (math.CT) #FOS: Mathematics #Geometric and Algebraic Topology #Homotopy and Cohomology in Algebraic Topology
paper · pdf · doi:10.48550/arxiv.1501.00792
openalex publication_date 2015/01/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Given any category C with pullbacks and a terminal object, we show that the data consisting of the objects of C, the spans of C, and the isomorphism classes of spans of spans of C, forms a bicategory. We denote this bicategory Span2(C) and show that this construction can be applied to give a bicategory of n-manifolds, cobordisms of those manifolds, and cobordisms of cobordisms.