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1. • CommentRowNumber1.
   • CommentAuthorDmitri Pavlov
   • CommentTimeFeb 12th 2025
   • PermaLink
   Author: Dmitri Pavlov
   Format: MarkdownItexRemoved a query: +-- {: .query} _Bruce_: I'm shooting in the dark here with this $\omega$-groupoid sentence above. Am I right? What does that boil down to concretely? =-- +-- {: .query} _Bruce_: What's a [[geometric stack]]? _Chris_: A stack is geometric if it is quasi-compact (any open cover has a finite sub-cover) and the diagonal morphism is representable and affine, though that probably doesn't help much. I don't know much about stacks yet, but maybe someone else can explain this. I think the point is that one needs some hypotheses to actually prove stuff for stacks. =-- <a href="https://ncatlab.org/nlab/revision/diff/geometric+infinity-function+theory/70">diff</a>, <a href="https://ncatlab.org/nlab/revision/geometric+infinity-function+theory/70">v70</a>, <a href="https://ncatlab.org/nlab/show/geometric+infinity-function+theory">current</a>

   Removed a query:

   +– {: .query} Bruce: I’m shooting in the dark here with this -groupoid sentence above. Am I right? What does that boil down to concretely? =–

   +– {: .query}

   Bruce: What’s a geometric stack?

   Chris: A stack is geometric if it is quasi-compact (any open cover has a finite sub-cover) and the diagonal morphism is representable and affine, though that probably doesn’t help much. I don’t know much about stacks yet, but maybe someone else can explain this. I think the point is that one needs some hypotheses to actually prove stuff for stacks.

   =–

   diff, v70, current