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Daniel Teixeira (Nov 30 2021 at 15:18):How is category theory in Canada, and in Montreal in particular? I am currently browsing through their for PhD programs there. I recently found out about Montreal's CT group, specially at McGill, but some sources suggests it's defunct right now.
edit: I know that Western has a few HoTT oriented faculty, and I know that at least Theo Freyd from Dalhousie/Perimeter uses higher categories in his work. Also Joyal is emeritus at UdeM. But McGill/UToronto/Concordia (and others) have immense departments, so it's hard to browse through their faculty
Morgan Rogers (he/him) (Nov 30 2021 at 15:22):I believe it's been defunct for a while; this was already effectively the case when I contacted Marta Bunge 4 years ago inquiring about PhD opportunities in category theory there (that was her assessment at the time, since she was retiring, or at least no longer in a position to take on PhD students).
Cole Comfort (Nov 30 2021 at 15:27):There is still category theory going on in Canada. From the computer science side of things, there is the conference FMCS which is attended by category theorists in Canada and their colleauges. Here is the 2019 program if you want to see who is active: https://pages.cpsc.ucalgary.ca/~robin/FMCS/FMCS2019/schedule.html
Ralph Sarkis (Nov 30 2021 at 15:36):Prakash Panangaden from McGill is still very active in category theory applied to CS (especially machine learning).
Jade Master (Nov 30 2021 at 19:23):Dorette Pronk and collaborators are doing category theory in Nova Scotia
Martti Karvonen (Nov 30 2021 at 19:27):At uOttawa there's Pieter Hofstra and Simon Henry, (and Phil Scott & Rick Blute with emeritus status, both still active) + their students and me with a temporary position.
John Baez (Nov 30 2021 at 22:30):The most active person I know in category theory at McGill is Prakash Panagaden:
I have three research areas: (a) semantics and logics for probabilistic systems and languages (b) theoretical aspects of machine learning (c) quantum information theory. I work on approximation of continuous-state systems and associated metrics and logics. I am working on a quantitative extension of equational logic which allows one to carry out approximate reasoning equationally. I have been working on Stone duality for Markov processes and completeness theorems for Markovian logics. I am also interested in duality for automata and using it for minimization. Recently I have begun working on diffusion and similar continuous-time Markov processes . I have not been active in quantum information theory for a while but I have just started working on it again.
John Baez (Nov 30 2021 at 22:33):Andre Joyal is quite active in a way, for example he's been working on infinity-topos theory with Damien Calaque and Mathieu Anel, but he's probably not taking students.
John Baez (Nov 30 2021 at 22:36):At Dalhousie Peter Selinger has built up a big group working on quantum programming languages, with a firm foundation in category theory. I think he's getting millions of dollars from DARPA or some other US agency.
Patrick Nicodemus (Dec 01 2021 at 04:43):John Baez said:
The most active person I know in category theory at McGill is Prakash Panagaden:
I have three research areas: (a) semantics and logics for probabilistic systems and languages (b) theoretical aspects of machine learning (c) quantum information theory. I work on approximation of continuous-state systems and associated metrics and logics. I am working on a quantitative extension of equational logic which allows one to carry out approximate reasoning equationally. I have been working on Stone duality for Markov processes and completeness theorems for Markovian logics. I am also interested in duality for automata and using it for minimization. Recently I have begun working on diffusion and similar continuous-time Markov processes . I have not been active in quantum information theory for a while but I have just started working on it again.
Barr is at McGill.
John Baez (Dec 01 2021 at 05:19):How active is Barr now? The last paper I know by him is from 2016, and he's retired (emeritus).
Alexander Campbell (Dec 01 2021 at 07:16):Barr had a couple of papers published in 2019 (see https://www.math.mcgill.ca/barr/#2010pres). He also gave a talk at the CT at Dalhousie in 2017.
Paolo Perrone (Dec 01 2021 at 08:33):There is also Walter Tholen in Toronto (York University), technically emeritus, but still active.
Morgan Rogers (he/him) (Dec 01 2021 at 09:33):John Baez said:
The most active person I know in category theory at McGill is Prakash Panagaden:
I have three research areas...
If the most active person you know in category theory doesn't mention category theory in their research interest, that doesn't sound so hopeful :grimacing:
Cole Comfort (Dec 01 2021 at 10:30):My master's supervisor Robin Cockett is still active at the University of Calgary.
Cole Comfort (Dec 01 2021 at 10:30):http://pages.cpsc.ucalgary.ca/~robin/
Matteo Capucci (he/him) (Dec 01 2021 at 11:00):Morgan Rogers (he/him) said:
John Baez said:
The most active person I know in category theory at McGill is Prakash Panagaden:
I have three research areas...
If the most active person you know in category theory doesn't mention category theory in their research interest, that doesn't sound so hopeful :grimacing:
If he has the same opinions on CT that Mardare (frequent collaborator afaik) has, I see why he didn't mention it. They don't consider themselves category theorists as much as someone working in <put classical math discipline here> wouldn't consider themselves set theorists.
John Baez (Dec 01 2021 at 12:29):Morgan Rogers (he/him) said:
John Baez said:
The most active person I know in category theory at McGill is Prakash Panagaden:
I have three research areas...
If the most active person you know in category theory doesn't mention category theory in their research interest, that doesn't sound so hopeful :grimacing:
Well, I know him pretty well and he's one of the more serious applied category theorists around. He doesn't do "pure" category theory - he uses category theory to do stuff.
John Baez (Dec 01 2021 at 12:31):I just checked, and I don't mention categories on my webpage either!
John Baez (Dec 01 2021 at 12:41):But anyway: YES, many of the most famous category theorists in Canada are retired and probably not taking students anymore. Another one that comes to mind is Robert Paré - he's also emeritus.
People who want to study category theory in Canada should think about Dorette Pronk, Robin Cockett, and... WHO ELSE???
What's Michael Makkai doing lately? He's at McGill.
John Baez (Dec 01 2021 at 12:46):I think one lesson here is: it's hard to get jobs in "pure" category theory because there aren't thriving research teams.
Cole Comfort (Dec 01 2021 at 12:48):There is also Geoff Crutwell
Cole Comfort (Dec 01 2021 at 12:54): John Baez (Dec 01 2021 at 12:54):Right! Geoff Crutwell is at Mount Allison and he now runs Theory and Applications of Categories (after Bob Rosebrugh, another oldster, also at Mount Allison, quit that job.) I now see he doesn't have any gray hair at all.
John Baez (Dec 01 2021 at 12:57):Rory Lucyshyn-Wright is at Brandon University, which I'd never heard of... but he's a really powerful category theorist, at least from what I can tell by studying his paper Enriched algebraic theories and monads for a system of arities. And he looks even younger than Geoff Crutwell!
Morgan Rogers (he/him) (Dec 01 2021 at 17:09):@Rory Lucyshyn-Wright and @Geoff Cruttwell are present on this Zulip channel, and might want to comment if they see this.
John Baez (Dec 01 2021 at 20:25):Luckily my remarks were purely complimentary. But yes, if they actually read this they could say more about who is actively taking grad student in category theory in Canada!
Steve Awodey (Dec 02 2021 at 01:47):John Baez said:
I think one lesson here is: it's hard to get jobs in "pure" category theory because there aren't thriving research teams.
UOttawa has been a thriving center for CT research for many years, with Phil Scott, Rick Blute, Pieter Hofstra, and a steady stream of postdocs and PhD students. Scott and Blute have recently gone emeritus (but are by no means out of the picture), and Simon Henry was then hired. I think that's still pretty thriving.
Steve Awodey (Dec 02 2021 at 01:50):I do think it's true that it's hard to get jobs in pure CT, but the reason is that it's hard to get jobs in any area of pure mathematics. Young category theorists in Canada are actually doing pretty well at getting jobs.
John Baez (Dec 02 2021 at 02:17):That's good to hear! Like who, where?
Steve Awodey (Dec 02 2021 at 05:10):Like Rory, Geoff, and recently Jason Parker from Ottawa, who just got a job (postdoc) at Brandon (Manitoba).
Morgan Rogers (he/him) (Dec 02 2021 at 08:49):John Baez said:
Luckily my remarks were purely complimentary. But yes, if they actually read this they could say more about who is actively taking grad student in category theory in Canada!
Oh yes, I was hoping that they would be able to tell us more about category theory activity happening in Canada, not respond to your comments :rolling_on_the_floor_laughing:
John Baez (Dec 02 2021 at 19:35):Steve Awodey said:
Like Rory, Geoff, and recently Jason Parker from Ottawa, who just got a job (postdoc) at Brandon (Manitoba).
That's good. Students should however note that this is just 3 people, and Geoff got his PhD twelve years ago - so the evidence that "young category theorists in Canada are actually doing pretty well at getting jobs in category theory" may be rather weak.
John Baez (Dec 02 2021 at 19:36):I just don't want anyone to suffer the consequences of over-optimism. Maybe there are a bunch more category theorists who've gotten jobs in Canada, but if so it'd be good to know who they are.
Martti Karvonen (Dec 02 2021 at 20:13):If by "getting a job" you mean tenure-track/tenure, then Simon Henry got hired at uOttawa in 2019. If you also count postdocs, there's more (e.g. me, Jason Parker, and JS Lemay at least).
Cole Comfort (Dec 02 2021 at 20:50):John Baez said:
Steve Awodey said:
Like Rory, Geoff, and recently Jason Parker from Ottawa, who just got a job (postdoc) at Brandon (Manitoba).
That's good. Students should however note that this is just 3 people, and Geoff got his PhD twelve years ago - so the evidence that "young category theorists in Canada are actually doing pretty well at getting jobs in category theory" may be rather weak.
Myself and some other Canadians I know chose to do our PhDs in Europe/UK because funding for fundemental research in Canada is quite rough... at least at the PhD level. Years of austerity from right wing governments takes its toll.
John Baez (Dec 02 2021 at 20:58):Do you have impressions about CT jobs in Canada?
John Baez (Dec 02 2021 at 20:59):Either postdocs or tenure track jobs?
Cole Comfort (Dec 02 2021 at 21:00):No, I have no experience with postdocs in Canada or professorships,. However, at the PhD level, the main way to get funding is from the NSERC doctoral scholarship and it is very competitive. If you are going to do a PhD in Canada it would be very much preferable to apply for a project which already has grant money to avoid trying to compete for the NSERC.
Jacques Carette (Dec 03 2021 at 13:19):The other way to get funded in Canada is to have a supervisor with a large enough NSERC grant that they can support a PhD student. Unfortunately most math profs don't have grants large enough to do that. But many profs in CS do. And there are CS profs who use a lot of category theory. In my own department, two of us (myself and Wolfram Kahl) for sure; there used to be Tom Maibaum too, but he retired.
Geoff Cruttwell (Dec 03 2021 at 13:43):I now see he doesn't have any gray hair at all.
Maybe not in pictures on the internet, but looking in the mirror recently I've noticed a few :)
For PhD programs in Canada, the three most likely places would be U. Ottawa (Pieter Hofstra, Rick Blute, Phil Scott, Simon Henry), Dalhousie (Peter Selinger, Dorette Pronk), and U. Calgary (Robin Cockett in the CS department, with some category-theory-friendly people like Kristine Bauer in the math department). My university (Mount Allison) doesn't have a Phd program, but I can supervise PhD students jointly with people at Dalhousie (I previously supervised Evangelia Aleiferi, and am currently supervising Marcello Lanfranchi, both jointly with Dorette). Brandon University (where Rory is) also doesn't have a PhD in math program, but he may also be able to jointly supervise with others (not sure, would have to contact him).
For postdocs, there has been a fair bit of recent success of category theory people getting national or regional postdoctoral fellowships in Canada: Rory got both an NSERC (national) and AARMS (Atlantic regional) postdoctoral fellowship, JS Lemay currently has an NSERC postdoc (working with me), Jonathan Gallagher just finished an AARMS postdoc (working with Dorette and myself), and Martin Szyld and Geoff Vooys both currently have AARMS postdocs (both working with Dorette). Michael Lambert is also working with me as a postdoc. Martti (at Ottawa) and Jason (at Brandon) were mentioned above. And I just remembered Matt Amy at Dal, who also has an AARMS postdoc! There's probably some more I'm missing as well...
For tenure-track positions, unfortunately I don't know of any right now. I would hope that Calgary, Ottawa, and Dal would continue to hire category-theory-related people, but one never knows how hiring will go.
Nicolas Blanco (Dec 03 2021 at 14:38):For postdocs, Neil Jr. Ross and Peter Selinger are offering one at Dalhousie right now. It is in quantum computing with an emphasis on mathematical, logical and categorical techniques. It has been advertised on the categories mailing list so I think it is worth mentioning it.
John Baez (Dec 03 2021 at 19:53):Thanks for the detailed information, Geoff! This should be really useful to would-be grad students and postdocs. I bet you got one more gray hair just from writing it all down.
John Baez (Dec 03 2021 at 19:54):Ideally the category theory community would have some sort of "database" of info like this, but Zulip threads are a start.
Mike Shulman (Dec 03 2021 at 20:18):Someone should make an nLab page.
Morgan Rogers (he/him) (Dec 03 2021 at 20:21):Isn't this exactly the kind of thing that @Christian Williams and co's database is indended to be for?
John Baez (Dec 03 2021 at 20:43):Yeah, sort of! I guess the initial organization was supposed to occur with people entering in facts about themselves... and then ultimately we could search the database in various ways.
John Baez (Dec 03 2021 at 20:45):However, Christian and @Joshua Meyers are young, without yet having achieved the iron discipline required to finish tiresome projects, so I believe they are off doing other things.
Mike Shulman (Dec 03 2021 at 20:46):How old do I have to get before I achieve that iron discipline?
John Baez (Dec 03 2021 at 20:46):It depends on how hard you work to achieve it!
Steve Awodey (Dec 04 2021 at 18:05):Mike Shulman said:
How old do I have to get before I achieve that iron discipline?
I'm sorry to tell you that it's not merely a question of age ...
Mike Shulman (Dec 04 2021 at 19:10):Oh darn. (-:
Ben MacAdam (Dec 08 2021 at 00:49):Isn’t Carlo Scandolo still tenure-track in the physics department at Calgary?
Fabrizio Genovese (Dec 08 2021 at 17:33):Yeah, he should be still there.
Joshua Meyers (Dec 09 2021 at 16:57):John Baez said:
However, Christian and Joshua Meyers are young, without yet having achieved the iron discipline required to finish tiresome projects, so I believe they are off doing other things.
We hope to build it very soon! See here if you want to join the effort.
Nathanael Arkor (Dec 09 2021 at 16:59):Joshua Meyers said:
John Baez said:
However, Christian and Joshua Meyers are young, without yet having achieved the iron discipline required to finish tiresome projects, so I believe they are off doing other things.
We hope to build it very soon! See here if you want to join the effort.
The stream is private, so people can't see any of the messages unless you invite them.
Joshua Meyers (Dec 09 2021 at 17:30):PM me if you want to be invited! Here is our notion if you want to see how we are thinking about this