New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
[Merged by Bors] - feat(topology/category/*/projective): CompHaus and Profinite have enough projectives #8613
Conversation
@@ -169,23 +170,27 @@ def limit_cone {J : Type u} [small_category J] (F : J ⥤ CompHaus.{u}) : | |||
{ X := | |||
{ to_Top := (Top.limit_cone (F ⋙ CompHaus_to_Top)).X, | |||
is_compact := begin | |||
dsimp [Top.limit_cone], | |||
show compact_space ↥{u : Π j, (F.obj j) | ∀ {i j : J} (f : i ⟶ j), (F.map f) (u i) = u j}, |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
All the changes to this proof are merely to speed it up so that it doesn't time out in my VScode.
Could we add a reference to an informal proof of these facts? Chapter 21 of https://www.google.com.au/books/edition/_/w6or65-Hw6UC?hl=en&gbpv=0 has CompHaus has enough projectives. |
Otherwise, looks great! |
I've added a reference. |
bors merge |
…ugh projectives (#8613) Co-authored-by: Adam Topaz <github@adamtopaz.com> Co-authored-by: Adam Topaz <github@adamtopaz.com>
Pull request successfully merged into master. Build succeeded: |
Co-authored-by: Adam Topaz github@adamtopaz.com