2023/08/31 by Fei Xu, Xu, Fei, Chenyou Zheng +1 · 2 citations
Mathematics · Medicine · #18A25 #18F10 #18F20 #20C20 #Algebraic structures and combinatorial models #Category Theory (math.CT) #FOS: Mathematics #Group Theory (math.GR) #Homotopy and Cohomology in Algebraic Topology #Intracranial Aneurysms: Treatment and Complications #Representation Theory (math.RT)
paper · pdf · doi:10.48550/arxiv.2308.16838
openalex publication_date 2023/08/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Given a general finite group G, there are various finite categories whose cohomology theories are of great interests. Recently Balmer and Grodal gave some new characterizations of the groups of endotrivial modules, via Čech cohomology and category cohomology, respectively, defined on certain orbit categories. These two seemingly different approaches share a common root in topos theory. We shall demonstrate the connection, which leads to a better understanding as well as new characterizations of the group of endotrivial modules.