You're reading the public-facing archive of the Category Theory Zulip server.
To join the server you need an invite. Anybody can get an invite by contacting Matteo Capucci at name dot surname at gmail dot com.
For all things related to this archive refer to the same person.
Blake Pollard (Jun 26 2020 at 17:38):This online conference is just wrapping up, but the videos of all the sessions are on YouTube:
https://av5.ljnet.it/icgt2020/online-program/
I'm sure a bunch of folks on here are aware of this event, but didn't see much discussion.
Morgan Rogers (he/him) (Jun 26 2020 at 17:52):Or any discussion at all, for that matter! Thanks for bringing it up. If you want to kick off discussions, what talk(s) did you enjoy? What novel things did you see at any of the talks you watched?
Blake Pollard (Jun 26 2020 at 18:16):Well, @Fabrizio Genovese gave a talk on joint work with @David Spivak on how the Grothendieck construction (well really category of elements I guess) gives a nice way of understanding the semantics of Petri nets with guards within the normal Petri net world.
John Baez (Jun 26 2020 at 18:16):I wish those folks had used this Zulip for discussions. :cry:
Blake Pollard (Jun 26 2020 at 18:19):But then there a bunch of talks on double and single pushout rewriting systems in the various contexts of graphs and graphs with 'attributes.' Also stuff on tool development (coming out of Glasgow I gather) to support for instance Milner's bigraphs. Watching the talks though it seems like there is an 'applications' layer that all this stuff is useful for, but it is harder to get an idea of what that looks like since the audience for these talks is the graph transformation community who I guess already gets why this stuff is relevant.
Blake Pollard (Jun 26 2020 at 18:23):The talk that I haven't watched yet, but am most interested in, is from Jean Krivine and Nicholas Behr on their rewriting setup aka tracelets and Kappa. Behr and others have some recent work where they start calculating expectation values of the presence of certain diagrams in stochastic graph rewriting. For that they use machinery (commutators) inspired by quantum and it just seems super dope, though it is definitely hard to understand the details. See https://arxiv.org/pdf/2003.09395.pdf and https://arxiv.org/pdf/2003.11010.pdf.
John Baez (Jun 26 2020 at 18:26):Blake Pollard said:
Watching the talks though it seems like there is an 'applications' layer that all this stuff is useful for, but it is harder to get an idea of what that looks like since the audience for these talks is the graph transformation community who I guess already gets why this stuff is relevant.
I've always had that problem learning theoretical computer science, ever since I was invited to a conference on it due to my work on n-categories. Learning a subject from the "top down", by which I mean starting from the most abstract end, is very nerve-racking because you don't know what's important or what's just cute. I'm so glad I learned physics from the "bottom up": in that subject, when I do abstract stuff, I know how or whether it's connected to anything useful. It may not be, but at least I know that.
John Baez (Jun 26 2020 at 18:27):I want to see stochastic graph rewriting really applied in chemistry!!!
Blake Pollard (Jun 26 2020 at 18:30):Sub, Spencer, and I had a chat the other day with Walter Fontana who is in systems biology at Harvard and he has been working with Daniel Merkle (part of the other MOD gang for rewriting in chemistry) and some other folks (Russ Harmer), who are working to bridge the gap to real applications. They have that postdoc ad up funded by the Danes that you posted on Azimuth. Lots of really interesting challenges, but things are definitely heating up!
Fabrizio Genovese (Jun 26 2020 at 23:05):Blake Pollard said:
Well, Fabrizio Genovese gave a talk on joint work with David Spivak on how the Grothendieck construction (well really category of elements I guess) gives a nice way of understanding the semantics of Petri nets with guards within the normal Petri net world.
Yes, it was the category of elements. But as I said in the talk we kept calling it "Grothendieck construction" because it sounded cooler.