Zulip Chat Archive
Stream: condensed mathematics
Topic: 9.4 for profinite S
Johan Commelin (Sep 16 2021 at 15:03):
To derive 9.4, there is one crucial place where we currently use that S is finite, namely 9.8. All the other stuff doesn't care about S.
I'm now thinking about how to generalize to profinite S.
The first 4 lines of the proof of 9.8 show how to prove it for profinite S. So we can do that, and then 9.4 for profinite S will follow. My impression is that this is the easiest way. (@Peter Scholze did you have a different path in mind for LTE, when it comes to reducing 9.4 for profinite S to the finite case?)
Peter Scholze (Sep 16 2021 at 20:29):
Johan Commelin said:
To derive 9.4, there is one crucial place where we currently use that
Sis finite, namely 9.8. All the other stuff doesn't care aboutS.
I'm now thinking about how to generalize to profiniteS.The first 4 lines of the proof of 9.8 show how to prove it for profinite
S. So we can do that, and then 9.4 for profiniteSwill follow. My impression is that this is the easiest way. (Peter Scholze did you have a different path in mind for LTE, when it comes to reducing 9.4 for profiniteSto the finite case?)
There are two paths: a) as in the manuscript, directly deal with profinite , which only requires a small extra step in 9.8; b) formally deduce 9.4 for profinite from 9.4 for finite by passing to a limit and using that weak exactness behaves well under passing to filtered colimits and passing to completions.
I originally presumed you would be taking path b). But you might as well take path a) if that's less trouble.
Last updated: May 02 2025 at 03:31 UTC