The Stacks project

Example 7.6.6. Let $\mathcal{C}$ be a category. There is a canonical way to turn this into a site where $\{ f : V \to U \mid f\text{ is an isomorphism}\} $ are the coverings of $U$. Sheaves on this site are the presheaves on $\mathcal{C}$. This corresponding topology is called the chaotic or indiscrete topology.

Comments (2)

Comment #5500 by Tim Holzschuh on

I think one needs to choose all sets of isomorphisms as coverings, right?

Comment #5701 by on

OMG, thanks very much! This is yet another mistake I made early on with the material on sites. The change is here.

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  • 2 comment(s) on Section 7.6: Sites

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View Example 7.6.6 as pdf