I've heard that in the category of sheaves over a topological space $X$, products of epimorphisms are not epimorphisms. I think that it's equivalent to saying that $\mathbf{Sh}(X)$ does not satisfy AB4. However I could not find an example.
2026-04-04 20:27:01.1775334421
Example of epimorphisms such that the product is not an epimorphism in the category of sheaves
949 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in SHEAF-THEORY
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