Most sources say descent is defining an object over $S$ using objects over $U_i$ for some cover $\left\{ U_i \right\}$ of $S$. If I replace the covering family with a single arrow $\coprod _i U_i\rightarrow S$, then it's not at all true that giving an object over each $U_i$ is the same as giving an object over $\coprod _iU_i$. How to resolve this?
2026-03-09 05:50:18.1773035418
Silly question about descent
237 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in CATEGORY-THEORY
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