2021/07/02 by Elmer, Jonatan · 1 citation
#20C20 #20J06 #FOS: Mathematics #Representation Theory (math.RT)
paper · doi:10.48550/arxiv.2107.00991
Let G be the Klein Four-group and let k be an arbitrary field of characteristic 2. A classification of indecomposable kG-modules is known. We calculate the relative cohomology groups H_\chii(G,N) for every indecomposable kG-module N, where \chi is the set of proper subgroups in G. This extends work of Pamuk and Yalcin to cohomology with non-trivial coefficients. We also show that all cup products in strictly positive degree in H_\chi^*(G,k) are trivial.