2021/07/20 by Ivo Dell’Ambrogio, Dell'Ambrogio, Ivo
Computer Science · #18B40 #18N10 #19A22 #20C99 #20J05 #55P91 #Category Theory (math.CT) #FOS: Mathematics #Group Theory (math.GR) #K-Theory and Homology (math.KT) #Representation Theory (math.RT) #Topological and Geometric Data Analysis
paper · pdf · doi:10.48550/arxiv.2107.09478
openalex publication_date 2021/07/20 · openalex created_date 2022/08/15 · openalex updated_date 2026/07/28
We extend the theory of Mackey 2-functors introduced in arXiv:1808.04902 by defining the appropriate notion of rings, namely Green 2-functors. After providing the first results of our theory and abundant examples, we show how all classical Green functors familiar from representation theory and topology arise by decategorification, in various ways, of some Green 2-functor occurring in Nature.