The Stacks project

  • the open covering $\mathcal{V}$ is a refinement of the open covering $\mathcal{U}$ (if $\mathcal{V} : U = \bigcup _{j \in J} V_ j$ and $\mathcal{U} : U = \bigcup _{i \in I} U_ i$ this means each $V_ j$ is completely contained in one of the $U_ i$),

Comments (2)

Comment #3222 by on

The refinement should cover the same set as the covering it refines, i.e., replace by .

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