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Are the injections of a coproduct a cover in the canonical pretopology?

This will not be the case in general. A family is a cover in the canonical topology if all its pullbacks are jointly regular epimorphism. So this will for example be the case if coproducts are ...
Simon Henry's user avatar
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10 votes
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Derived category of local systems of finite type on a $K(\pi,1)$ space: an explicit counterexample

I can give an example that is even a smooth complex algebraic variety that shows up naturally in algebraic geometry. Let $X$ be the moduli space of abelian varieties of genus $g>1$ with full level $...
Will Sawin's user avatar
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