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Stream: community: events

Topic: Category Theory Octoberfest 2025

James Deikun (Oct 25 2025 at 12:50):

This starts in less than 15 minutes! Looks like a lot of good talks too.

James Deikun (Oct 25 2025 at 12:58):

Website at https://richardblute.ca/octoberfest-2025/ btw.

James Deikun (Oct 25 2025 at 14:45):

A very basic question about the talk by Tim Luders: by $O(n)$ is it meant not the Lie group, or the topological group, but a group structure on a combinatorial space (e.g. Kan complex) that is equipped with a weak homotopy equivalence to the topological group $O(n)$ preserving the group structure?

John Baez (Oct 25 2025 at 14:50):

I don't know what he meant, since I didn't attend the talk, but a homotopy theorist would often feel fine using language in the way you suggest, while a differential geometer might be scared to.

David Michael Roberts (Oct 25 2025 at 20:20):

Could be any model of $\Omega BO(n)$ (constructed as a homotopy pullback of the basepoint with itself), for any model of $BO(n)$

Bryce Clarke (Oct 26 2025 at 12:58):

This starts again in 2 mins!

James Deikun (Oct 26 2025 at 13:01):

And with a second answer to the question "What is a space?"

James Deikun (Oct 26 2025 at 13:28):

I feel like that was kind of a failed talk because so much time was spent on intro stuff that he didn't really get to the original contributions.

James Deikun (Oct 26 2025 at 17:27):

Back from lunch in 3 minutes with Exponentiable Virtual Double Categories and Representability by @Ea E T (they/them) . This is the home stretch!

Théo Tyburn (Oct 26 2025 at 22:58):

Are there some recordings of the talks? Couldn't attend unfortunately.

James Deikun (Oct 26 2025 at 23:38):

There are supposed to be, they were certainly recorded, but it's going to take a while for them to show up.

Jean-Baptiste Vienney (Oct 27 2025 at 06:55):

I can’t speak for Rick but I think they will be on the website in something like 10 days :)