I have been studying cohomology (sheaf cohomology and Čech cohomolgy) and I have an intuition of what the first cohomology group means. For example, the first derived functor measures to what extent the functor is exact. In the case of sheaf cohomology, it measures the obstruction to exactness of the 'taking sections' functor. In the (more geometrical) context of Čech cohomology it is similar, studying the obstruction of the local sections to be extended to global section. But I have no intuition of what the second (and higher) cohomology groups measure.
2026-03-27 04:23:31.1774585411
Significance of second (and higher) cohomology groups
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