David Wigner showed that the group cohomology invented by Calvin Moore can be related to sheaf cohomology when the coefficient is discrete by constructing a locally constant sheaf on the classifying space of the group. In the case where the group action is trivial, the computation is simple since we reduce the sheaf cohomology to a simpler topological cohomology. However, when the group action is non-trivial, I am not sure how to perform computations. Perhaps, we can reduce the problem to Čech cohomology in some way. Maybe, there are some other techniques. Is there any reference from which I can learn how to do explicit computations?
2026-02-22 21:51:15.1771797075
How to compute sheaf cohomology of a classifying space?
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