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John Baez (Feb 21 2025 at 21:31):Here's an announcement from the ACT Steering Committee:
The current plan is for @Pawel Sobocinski and @Priyaa Varshinee to run the conference Applied Category Theory 2026 in Tallinn, Estonia: they are at the Tallinn University of Technology. There's a chance this may not happen, only because of the inherent unpredictability of life, so don't buy your tickets just yet - but this is the plan. We thank Pawel and Priyaa very much for volunteering to do this.
James Fairbanks (Feb 22 2025 at 00:09):This is great news! I’m looking forward to it!
John Baez (Feb 26 2025 at 21:31):The ACT conference steering board wants to require all future organizers to live stream the conference. @Pawel Sobocinski and @Priyaa Varshinee have agreed to live stream ACT 2026.
JR Learnstomath (Jun 18 2025 at 06:12):@Pawel Sobocinski @Priyaa Varshinee , could someone volunteer to help organize if they are not physically in Tallinn and/or may not be able to go in person?
John Baez (Oct 27 2025 at 16:19):The next annual conference on applied category theory is in Estonia!
For more details, read on!
John Baez (Oct 27 2025 at 16:20):Deadlines
The conference particularly encourages participation from underrepresented groups. The organizers are committed to non-discrimination, equity, and inclusion. The code of conduct for the conference is available here.
Program Committee Chairs
Program Committee
Teaching & Communication
Organizing Committee
Steering Committee
Elena Di Lavore (Dec 01 2025 at 08:27):Could we please have more details on the new proceedings track about teaching and communication?
As a PC member, I did not receive any information about this new route to publication. I am surprised that a decision that changes the scope of the proceedings was taken without consulting the community nor notifying the PC. Do we have an expert and diverse enough PC to cover the science of teaching? How do we evaluate teaching submissions against papers in applications of category theory?
I believe that the rest of the PC was not informed and never agreed to these changes. So I would like to initiate some open discussion about it.
Paolo Perrone (Dec 01 2025 at 09:21):Wait, what?
(I'm all for teaching and communication, you all know that, but who decided this?)
Chad Nester (Dec 01 2025 at 09:34):I think it would also be good to clarify exactly what the difference would be between a "research" submission and a "teaching and communication" submission. I don't understand what is meant by the latter. Are there any published articles that would fit this category?
Joe Moeller (Dec 01 2025 at 09:40):I think the right people to talk to might be Priyaa or Pawel, neither of which comes on here much.
Chad Nester (Dec 01 2025 at 09:43):I'll point out that the conference has a steering committee (see John's post above), which I would hope was involved. John is on the steering committee, so might know something about it.
John Baez (Dec 01 2025 at 10:15):The idea is to allow papers about the teaching and communication of applied category theory. It's the job of the program committee chairs (@Geoff Cruttwell and @Priyaa Varshinee) to decide on such things and communicate them to the program committee. Priyaa told us (the steering committee) that she'd been discussing this new policy with someone on the program committee, so I assumed that everyone on the program committee had at least heard of this. The program committee shouldn't first find out by reading a public announcement.
Anyway, @Elena Di Lavore and @Paolo Perrone, please raise your concerns with Priyaa and Geoffrey.
Martti Karvonen (Dec 01 2025 at 16:04):Hearing this, I can't help avoid thinking that this could've been created specifically to create space for a similar talk/proceedings paper as the special session on education at QPL 2025, but I hope I'm just jumping to conclusions.
Mario Román (Dec 01 2025 at 20:21):I did write to Priyaa and Geoff, multiple times already, raising these concerns.
They told me that, after discussing with some members of the Steering, they had decided to keep course anyway.
I still think this extra proceedings track should be reconsidered.
Joe Moeller (Dec 01 2025 at 21:12):Martti Karvonen said:
Hearing this, I can't help avoid thinking that this could've been created specifically to create space for a similar talk/proceedings paper as the special session on education at QPL 2025, but I hope I'm just jumping to conclusions.
I haven't been keeping up with QPL. What happened with the session on education that makes it something not worth trying to emulate?
Martti Karvonen (Dec 01 2025 at 21:18):The category was created ad hoc so that the singleton paper that ended up in that category would not be rejected as out of scope. I guess this time the category exists already during the CfP, but if it was created with that paper/some of the authors in mind (let alone them having influenced the matter), I don't think it's ideal as a process.
Joe Moeller (Dec 01 2025 at 21:29):That doesn't sound great. Given how much energy Priyaa has put into trying to increase outreach and education broadly for several years, it's hard to imagine this is something comparable. This point doesn't seem to relate directly to the original point though.
Joe Moeller (Dec 01 2025 at 21:37):I agree with the point that the PC should be chosen so as to be qualified to evaluate along the tracks. At what point specifically should the organizers have done something different knowing they wanted to do this?
John Baez (Dec 01 2025 at 23:13):Two people on the PC are explicitly listed under "Teaching & Communication". Presumably they can evaluate papers in these fields. I doubt people who don't want to referee such papers will be forced to. (I certainly hope not!)
Mario Román (Dec 01 2025 at 23:32):Joe Moeller said:
At what point specifically should the organizers have done something different knowing they wanted to do this?
I think I disagree even with the idea that the PC chairs may unilaterally create a different route to publication, for a topic they are particularly invested on, with different referees, and outside the usual scope of the conference. We would not want ACT proceedings to become a game of Calvinball.
Perhaps a special session or a non-proceedings track could be a more reasonable first experiment. I think the extra proceedings track should be removed.
And in any case, as John said before, the program committee shouldn't first find out by reading a public announcement.
Joe Moeller (Dec 01 2025 at 23:43):I hadn't noticed the separate section in the PC list with teaching and communication people. Now I think I'm getting on the same page.
Jules Hedges (Dec 02 2025 at 12:17):For comparison to prior art, if I remember correctly I sort of unilaterally created the tool demo track in ACT22 (by which I mean I said I wanted to do it and none of the other organisers objected so then it happened). I think tool demo papers were talk-only and not published. I don't remember there being any controversy about it
Elena Di Lavore (Dec 12 2025 at 15:27):Is the extra proceedings track still happening?
If so, no one has contacted the PC yet. But given everyone's reaction, maybe it should be reconsidered.
Bryce Clarke (Feb 12 2026 at 13:05):Has there been a first call for papers sent out already? I could not find it in my email (I know the information is available on the webpage)
Pawel Sobocinski (Feb 12 2026 at 14:01):Yes it has -- Priyaa has been sending it out to various mailing lists. It was sent out on the CT mailing list on 27 October 2025.
Chad Nester (Feb 12 2026 at 14:06):Sure enough:
#community: mailing list mirror > Applied Category Theory 2026: First Call for Papers
Chad Nester (Feb 12 2026 at 14:07):The link to the "detailed call for papers" seems to be broken (possibly an artifact of mirroring the mailing list on Zulip), but there's a working link to the cfp closer to the beginning of the message.
Mario Román (Feb 25 2026 at 15:57):Elena Di Lavore said:
Could we please have more details on the new proceedings track about teaching and communication?
As a PC member, I did not receive any information about this new route to publication. I am surprised that a decision that changes the scope of the proceedings was taken without consulting the community nor notifying the PC. Do we have an expert and diverse enough PC to cover the science of teaching? How do we evaluate teaching submissions against papers in applications of category theory?
I believe that the rest of the PC was not informed and never agreed to these changes. So I would like to initiate some open discussion about it.
Dear all,
Some of us have privately circulated and presented an open letter to the Steering Committee on this matter.
However, the Steering communicated to us that they decided that these proceedings—which were announced without the consent or previous consultation of the program committee—will still be submitted and reviewed at this conference and will be "published in a separate companion volume".
We want to ask for utmost respect for the work of the Steering and the work of the Chairs.
At this point, some of us may wish to stop serving this year's edition of the conference. We may feel that we have not been informed as honestly as possible when invited to serve to this conference; we may feel that teaching deserves to be valued more seriously than this; we may feel that the communication with the Program Committee is insufficient and lacking transparency; we may feel that it is unfair that the program committee and the broader community were never consulted; and we may feel that strong decisions about this edition of the conference have been imposed by a small subset of our community.
While keeping all due respect to all parties: We invite our colleagues at the Program Committee of ACT26 to reconsider if they wish to continue serving at ACT, at least during this year's edition.
We want to ask for utmost respect for any Program Committee member that wishes to stop serving ACT at least for this year. We ask that they are allowed to do so freely, without any kind of coercion or threat to their careers.
Respectfully,
Mario
Kevin Carlson (Feb 25 2026 at 18:04):John Baez said:
Two people on the PC are explicitly listed under "Teaching & Communication". Presumably they can evaluate papers in these fields. I doubt people who don't want to referee such papers will be forced to. (I certainly hope not!)
I'd just add to this that, while there are now three people on the T&C committee, only one actively publishes in the field this subcommittee will be assessing submissions in, as far as I can tell.
Matteo Capucci (he/him) (Mar 03 2026 at 08:58):No other response from the steering commit?
Chad Nester (Mar 03 2026 at 09:10):Personally, I don't think this passes the sniff test.
Chad Nester (Mar 03 2026 at 09:12):I would like the conference to succeed in the long term, and for it to become a respectable publication venue for our community. I think this sort of thing undermines these goals.
Chad Nester (Mar 03 2026 at 09:15):I encourage anyone who shares my concerns to sign the open letter. While nothing seems likely to come of it in the short term, if enough people sign it we can use it to initiate a conversation about this at the conference itself this summer.
John Baez (Mar 04 2026 at 22:16):The Steering Committee has been talking about this with anyone who emails us for quite some time now. Recently one committee member emailed Barbara Konig and Matteo Mattuci and asked if the latest plan alleviates their previously voiced concerns. Barbara said it did while Matteo said he still had some concerns (which he listed; he can do it again here if he wants).
The latest plan is to have three volumes:
Since the call for papers has already gone out, and the committees to review papers have already been constituted, I think the most reasonable course of action is to not try to suddenly change everything now, but instead keep discussing these issues to decide how things should work for ACT2027.
One problem is that some people with objections to the idea of publishing papers about teaching and communication are talking here, but people who support this idea (like the Program Committee Chairs, and the Steering Commitee) are mainly communicating somewhere else: by email.
Discussions here are fine as far as they go, but as far as I can tell, nobody on the Steering Committee but me regularly reads this Zulip.
I've already tried to assuage this problem by pointing the other Steering Committee members to the conversation here. I'll do it again, and also point out the open letter. However I do recommend that people with concerns email the Steering Committee and especially discuss this at the business meeting at ACT2026: that's a meeting specially designed for discussing the future of the ACT conference.
Just so there's no mystery about it, the Steering Committee is
Nathanael Arkor (Mar 05 2026 at 06:11):Are "extended research proceedings" the combination of the research and teaching proceedings, or something else?
Nathanael Arkor (Mar 05 2026 at 06:12):(If the former, I'm wondering why everything would need to be published twice, in addition to how teaching is relevant to the stated aims of compositionality, but perhaps I'm misunderstanding.)
John Baez (Mar 05 2026 at 06:20):I think the idea is that while initial submissions of research papers to ACT2026 have a rather tight page limit (12 pages), and EPTCS will publish those submissions that are accepted, authors of some of the best papers will be invited to write longer "extended" papers to submit to Compositionality, to be refereed again there.
Nathanael Arkor (Mar 05 2026 at 07:54):Would that function any differently from the authors choosing to submit papers to Compositionality independently?
Jules Hedges (Mar 05 2026 at 11:27):John Baez said:
Discussions here are fine as far as they go, but as far as I can tell, nobody on the Steering Committee but me regularly reads this Zulip.
May I suggest that this is a problem? This platform seems to be where the majority of the ACT community talk to each other, it feels like the steering committee might be disjoint to the majority of the actual community they serve
Mario Román (Mar 05 2026 at 11:59):John Baez said:
One problem is that some people with objections to the idea of publishing papers about teaching and communication are talking here, but people who support this idea (like the Program Committee Chairs, and the Steering Commitee) are mainly communicating somewhere else: by email.
Respectfully, I think this is a mischaracterization. People has objections to the idea of creating, without the consent of the PC, ad-hoc proceedings tracks reviewed by a few non-necessarily experts. And people have been explaining the problem since October 2025 by email.
Ralph Sarkis (Mar 05 2026 at 12:15):After communicating this letter to the Steering committee, we got two answers. The first was completely dismissive of our concerns. It only argued that pedagogy is an important part of research, even if we had clearly stated our agreement with this point. It was also not very nice.
The second answer clearly stated the intent of separating the proceedings, but it did not discuss our concerns, and seemed to try to refute our (verifiable) claim that the PC was not consulted.
That did not invite further communication with the committee. Your message is more inviting.
Could you (=committee) be more transparent about the decision?
For example, what made you change your mind about having only one proceedings? Which parts of the letter do you agree with, and which parts don't you agree with?
Can you give a more precise description of the kind of contributions you invite in this new track? If you can provide examples, that would help. What are the evaluation criteria that the specialized PC will use?
What do you expect the negative impact of cancelling the call for papers will be? Has anyone expressed intent in submitting to this track?
Elena Di Lavore (Mar 05 2026 at 13:39):but people who support this idea (like the Program Committee Chairs, and the Steering Commitee) are mainly communicating somewhere else
In addition to answering the questions above, could you please communicate here any argument that supports having a separate teaching and communication proceedings reviewed by a parallel PC of three members? or, at least, communicate these arguments to the PC members?
Pawel Sobocinski (Mar 05 2026 at 14:23):I've stayed out of this conversation until now, but let me add my 2 cents.
I'm really disappointed by how this issue has been handled. We are still a relatively new community and these sorts of heated controversies don't help.
I think the PC chairs should have had a proper engagement with their PC, instead of using the SC as some kind of stick to beat the rest of the PC with. I've never seen anything like this in 20+ years of being on PCs, SCs and organising/hosting conferences: normally these are very collegial affairs with everyone doing their best to ensure the best outcomes.
I don't want to get personal, but I guess that this is due to the inexperience of some of the people involved, but also due to mixing different academic traditions -- certainly maths conferences are less formal events that do not carry (and are not expected to carry) the same prestige as top CS conferences. But prestige is important for younger researchers who need to establish themselves and strengthen their CVs. And, unfortunately, ACT has not thus far been doing a good job of establishing itself as a quality venue -- at least based on what I've been hearing from various people in my own network. We don't want to end up in a situation where an ACT paper is a CV red flag, like an MDPI paper or IEEE Access.
To get to the controversy itself: I still don't understand why there needs to be a published volume of T&C contributions -- the way I understood the initial idea was that the role of the additional three person PC was to curate a T&S conference session based on submitted abstracts/short papers where these topics could be discussed in the community: best practices, success stories, etc. I think this would be both a fun thing to attend and a valuable opportunity to discuss more meta aspects of our work. A few talks, maybe a panel.
What is and what is not written in the original CFP is not that important imo -- plans change all the time. The number of people affected is, I assume, extremely small anyway: who knows how many submissions this T&C track will attract? 2-3?
If publication is really an issue for somebody, a compromise we have also discussed within our group in Tallinn could be to kick the publication arrangements into the future (e.g. a special issue of some Mathematics education journal edited by the PC chairs) if the quality of the submissions merits it.
John Baez (Mar 05 2026 at 18:09):Nathanael Arkor said:
Would that function any differently from the authors choosing to submit papers to Compositionality independently?
This plan would produce a volume of Compositionality called something like "Proceedings of ACT2026". Journals often have special issues devoted to conference proceedings, and this would be like that. That's all I know.
For those who haven't been following the drama:
For several years there has been a heated argument involving many people about whether the conference proceedings of ACT should be published in Compositionality. Originally the plan was to do this, but some editors of Compositionality argued that it would lower the standards of that journal, because the review process suitable for a 12-page talk are - so they argued - lower than those of a typical paper in Compositionality. The people making this argument were mainly mathematicians, who generally don't take conference proceedings seriously. On the flip side of the argument were mainly computer scientists, who often take conference proceedings very seriously. I see the whole argument as arising from how applied category theory blends different academic cultures.
For the last couple of years, the people against publishing proceedings in Compositionality had won, and the proceedings were published in Electronic Proceedings of Computer Science.
In the new plan, anyone whose 12-page research abstract gets accepted for ACT2026 gets to publish in ETPCS, as before, but also the program chairs will choose some of the best papers and nominate them to be expanded and turned into papers that would be submitted to Compositionality.
I believe this plan is an attempt to compromise between warring factions, and that accounts for its rather ungainly nature. Perhaps this issue should be decided by a large tag-team wrestling match at the business meeting of ACT2026.
John Baez (Mar 05 2026 at 18:14):Jules Hedges said:
John Baez said:
Discussions here are fine as far as they go, but as far as I can tell, nobody on the Steering Committee but me regularly reads this Zulip.
May I suggest that this is a problem? This platform seems to be where the majority of the ACT community talk to each other, it feels like the steering committee might be disjoint to the majority of the actual community they serve
I actually don't think this is the platform where the majority of the ACT community talk to each other. Maybe it was once. But very few of the people working at Topos, Topos UK, the Safeguarded AI project post here any more. Those are three of the main employers of applied category theorists!
For example Brendan Fong and David Spivak and David Jaz Myers and Sophie Libkind never post here anymore, and I haven't seen you here for about a year. Mike Shulman used to post here a lot, and a bunch of trans people seem to left the forum for that reason. But Mike, too, hasn't posted here much since December.
My guess is that many people of these people are too busy, and have enough people to talk to already.
(Of course, I can't tell if people who is reading but not posting, or posting in private channels here. For example there's a research team including @Nathaniel Osgood, @ww, @Xiaoyan Li, @Kris Brown, @Evan Patterson and myself who a lot in a private channel here. I'd prefer that all this was public, because the main reason for it being private is simply that it might bore other people... but I like doing things in public more than 99% of people.)
John Baez (Mar 05 2026 at 18:30):As a result, I don't know any public forum where most of the people who go to the ACT conference can be expected to be present for discussions regarding this conference.
John Baez (Mar 05 2026 at 18:38):Ralph Sarkis said:
Could you (=committee) be more transparent about the decision?
You just asked 6 questions, not counting the above one:
For example, what made you change your mind about having only one proceedings? Which parts of the letter do you agree with, and which parts don't you agree with?
Can you give a more precise description of the kind of contributions you invite in this new track? If you can provide examples, that would help. What are the evaluation criteria that the specialized PC will use?
What do you expect the negative impact of cancelling the call for papers will be? Has anyone expressed intent in submitting to this track?
I can't really answer these questions on my own and say these are the committee's answers, since other committee members will have different opinions. The whole committee has to deliberate to produce official answers to question.
Nor do I volunteer for the job of taking these questions of yours, copying them into an email to the committee, discussing them, then reporting back here - and then repeating this process many times, because surely people here will have followup questions.
It's really better to email the whole committee at once. If you want I can provide all our email addresses. But it sounds like maybe you have them?
It's even better to do what I suggested earlier: have a discussion of this at ACT2026. As Pavel hinted, we probably wouldn't be having this problem if major decisions about the ACT conference proceedings were made at the business meeting.
David Spivak (Mar 06 2026 at 16:37):Hi all,
On Feb 24, we responded the following (below my signature) to Elena and Mario, and I supposed they would pass it on to the other signatories; I'm not sure if they did or not. I'm sorry I didn't post it here. I don't check this often, though I have now read through this thread. I understand that our response does not address every concern, nor were we aware of every potential solution, that has been discussed here. We continue to think about how we can best serve the community.
Best,
David
Dear Elena, Mario, (and other signatories),
Thank you for writing. Bob's comments [not included here] were his own and were not deliberated on by the larger committee. However, the steering committee has been actively deliberating this issue for the past week, and we communicated our decision to the PC chairs a few days ago.
The T&C session and submission process will continue as planned. However, T&C proceedings papers will be published in a separate companion volume rather than in the main research proceedings. We believe this is the structurally-correct approach: T&C papers and research papers serve different audiences and have different evaluation criteria, and a separate volume lets each stand on its own terms.
We want to be clear that we take the integrity of ACT proceedings seriously, and we appreciate that the signatories do as well. We also want to note that the PC chairs followed the process available to them—consulting the steering committee and notifying the full PC—and have been doing difficult, unpaid work on behalf of the community. We ask that everyone engage with them respectfully as they implement this adjustment.
For future years, the steering committee will establish a written policy requiring that new proceedings tracks receive full committee deliberation and PC consultation before the CFP is published.
Best,
David, on behalf of the ACT Steering Committee
Jacob S. Zelko (Mar 23 2026 at 15:15):Quick question: when submitting a paper on EasyChair, I see this for the title and abstract instructions:
The title and the abstract should be entered as plain text, they should not contain HTML elements.
However, my abstract does contain LaTeX; should I remove the LaTeX somehow? Or is it fine to keep?
Geoff Cruttwell (Mar 23 2026 at 18:13):The system only accepts text, so if you enter LaTeX, it will just appear as the corresponding code. If that's easily readable, then it's ok, but if it's anything complicated, it might be better to try and make a text-only version.
Joe Moeller (Mar 23 2026 at 18:49):So if I'm only submitting a talk proposal, I am still uploading a pdf under "files"? Or am I just submitting a text-only abstract in the title and abstract section?
Monte Mahlum (Mar 24 2026 at 00:34):Hi all, it seems that the submission portal has closed although the deadline has yet to pass. Is anyone else experiencing this issue?
Joe Moeller (Mar 24 2026 at 00:36):Yes, this is the case for me too. @Priyaa Varshinee @Geoff Cruttwell
Valeria de Paiva (Mar 24 2026 at 01:08):yep, same here.
Joe Moeller (Mar 24 2026 at 03:13):Well, I hope they extend the deadline or something.
Monte Mahlum (Mar 24 2026 at 03:24):My plan is to email the organizers a copy of my would-be submission and hopefully that will be sufficient for now.
Chad Nester (Mar 24 2026 at 03:52):Me too. I've uploaded an abstract for one submission, but cannot currently upload the corresponding PDF.
Geoff Cruttwell (Mar 24 2026 at 10:19):Hi all -
My apologies - unfortunately, both new submissions and updates were closed early accidentally. Both should be open now, and we'll accept new abstract submissions until March 24th AOE.
All the best,
Geoff
Jules Hedges (Mar 30 2026 at 09:25):Could someone from the ACT PC dm me please!
(I think the PC chairs have an outdated email for me and I didn't succeed to get in contact with them and I suspect I might have missed bidding or something)
Nathaniel Virgo (Mar 30 2026 at 16:35):Can I assume that all we need to do for a talk proposal is not upload a pdf?
fosco (Mar 30 2026 at 16:36):I am also confused by the fact that so many submissions are missing a pdf. What should a referee judge from two (2) sentences and a title?
Jules Hedges (Mar 30 2026 at 16:38):The deadline for pdfs is still in the future, or at least I hope it is because I'm writing mine later
Jules Hedges (Mar 30 2026 at 16:39):I was assuming that talk proposals still need an extended abstract in pdf
fosco (Mar 30 2026 at 16:40):Ah, I see, I probably misremembered the final-final deadline
Nathaniel Virgo (Mar 30 2026 at 16:41):The deadline is Monday AoE, which I believe is (though I'm not completely sure, it could be an hour before or after that)
Nathaniel Virgo (Mar 30 2026 at 16:41):I guess there won't be an extension?
Jules Hedges (Mar 30 2026 at 16:42):Nathaniel Virgo said:
Can I assume that all we need to do for a talk proposal is not upload a pdf?
From the cfp:
Nathaniel Virgo (Mar 30 2026 at 16:42):how extended is an extended abstract in this community, typically?
Nathaniel Virgo (Mar 30 2026 at 16:42):It's just that on EasyChair there's no way to indicate if it's a talk or paper submission - there's a text box for an abstract, which is what I assumed we needed to fill out, and then you can also upload a pdf, but I'd assumed that was only for papers
fosco (Mar 30 2026 at 16:45):I, and several other authors, made it clear in the title:
"A very important theorem (talk proposal)"
"A proof of everything (extended abstract)"
Jules Hedges (Mar 30 2026 at 16:46):I don't remember if it's possible to have checkboxes for this if you configure easychair correctly, but I expect we will muddle through
Jules Hedges (Mar 30 2026 at 16:48):Nathaniel Virgo said:
how extended is an extended abstract in this community, typically?
The instructions say 1-2 pages and that matches what I call an extended abstract
Nathaniel Virgo (Mar 30 2026 at 16:51):I must have read that 3 or 4 times and not seen "one or two pages" - thanks for mentioning it, I'll prepare a pdf
Jules Hedges (Mar 31 2026 at 09:42):I look forward to the crossover event of the century between this thread and #community: general > AI-generated papers
Matteo Capucci (he/him) (Mar 31 2026 at 11:02):lmao
Martti Karvonen (Mar 31 2026 at 12:11):There were some submissions that I think would fit in this intersection (although it's not like the PC should have their discussions on papers in public), but at a quick glance they were fewer than I was worried about.
Jules Hedges (Mar 31 2026 at 12:27):Yep I wrote that before I read all the abstracts, now I have read them I will :zip_it:
Martti Karvonen (Mar 31 2026 at 12:30):More generally, I think ACT and other conferences might want to have some policies around LLMs, their role in submissions & disclosing LLM-use.
John Baez (Apr 01 2026 at 18:52):Indeed, I'll bring this to the attention of the ACT steering committee, and maybe we can work with the PC chairs and PC to develop some policies for this and especially future ACT conferences. I imagine things will keep changing. People should discuss this at the business meeting in Tallinn, too.
Jonty Male (May 18 2026 at 10:26):Is there any travel/registration fee support available for students?
Chad Nester (May 19 2026 at 09:55):I am trying to register for the conference, and there's a field on the conference form I don't understand.
Specifically, There is a mandatory field asking for a 'registry code'. What is this?
Chad Nester (May 19 2026 at 09:56):Ah: the field is only mandatory if I also want an 'e-invoice', which I guess just means I don't want one of those.
Bruno Gavranović (May 26 2026 at 12:24):Since when has ACT become so expensive?
Bruno Gavranović (May 26 2026 at 12:25):I'm genuinely curios as to what the costs are here, as that'd make it easier to justify paying them. This price point is reaching levels of some of the biggest deep learning conferences (e.g. NeurIPS) which, last year, for instance, hosted ~18k participants. It does not seem like this years ACT is that much different than the others (which were free, or had a negligble cost), so I am curious as to what changed.
Pawel Sobocinski (May 26 2026 at 12:30):These are already subsidised by what we hope will be a 30k donation which allowed us to significantly lower registration fees. I honestly don't know other conferences that are this cheap for 5 days with catering, room rental, invited speakers, and conference dinner included.
Morgan Rogers (he/him) (May 26 2026 at 14:02):Given that the ever-inflating price of conferences is consistently controversial, I don't think that's much of a defense of the price, Pawel. I am also curious what those different components run to.
Jules Hedges (May 26 2026 at 14:18):I don't want to cause a big argument because I know very well that organising conferences is really really hard. But for comparison, if I remember correctly our entire budget for ACT 2022 was roughly USD 11k, a bit of which came from the registration fee of GBP 20 (which I chose to do because we needed an accurate estimate of attendance under the university's covid rules, although the amount it raised was nice in a pinch). Importantly this was just for the conference, the adjoint school had its own funding. The vast majority of that went to funding travel for PhD students, with a bit on catering, and we had essential no other costs: the room hire was free (if a university doesn't let you hire a room for free for academic events I question what the purpose of a university is) and ACT had no invited speakers for the majority of its existence, I don't know why that suddenly became a thing recently
Jules Hedges (May 26 2026 at 14:20):If I remember correctly we decided to pay for only coffee and snacks but not for lunch to bring costs down, so everybody had to go outside to buy their own lunch. That's something that was feasible at Strathclyde but not at Taltech because of the location, I imagine
Niels van der Weide (May 26 2026 at 16:31):Based on what I see, these prices are the norm at theoretical CS conferences. One of the biggest factor for these prices, is catering since food prices have been increasing since 2022. Other conferences tried to combat high registration fees using several tactics:
However, it remains challenge to guarantee affordable registration. In my experience, organisers are very transparent regarding their expenditures, and why the prices are what they are.
Pawel Sobocinski (May 26 2026 at 18:17):if a university doesn't let you hire a room for free for academic events I question what the purpose of a university is
There are different kinds of universities. Some, really highly rated ones that understand the purpose of a university, keep all of the money centrally because of essential costs like paying their Vice Chancellors 450k a year, with a private chauffeur and a mansion, while paying their junior researchers starvation wages. Others, like Tallinn University of Technology, are more decentralised -- teaching money gets distributed to the faculties depending on the number of students, and the rest (research income etc.) is up to the faculties/departments.
Unfortunately our faculty/department doesn't have great rooms to host a conference. Another faculty, based at Kopli, does. They have to pay their staff, their building insurance, their cleaners, etc. It is absolutely normal that they charge money for this, since as I said, big university daddy doesn't really help very much. The charge for the rooms for the week is 6600 euros.
Altogether, budget / #expected participants works out to just under 600 euros per paying participant. Because several people (especially Sofie Taskova) have worked very hard to get additional sponsorship, we have been able to keep the conference fees as low as they are.
Morgan Rogers (he/him) (May 27 2026 at 15:28):What's included in the price for the rooms out of the price of the staff, cleaning and insurance? What are the other components costing? I don't want to belittle the efforts to cover some of the costs, but it would be a relief to have more of the transparency that Niels mentioned.
Pawel Sobocinski (May 28 2026 at 07:11):Dear Morgan -- I find it deliciously ironic that you're asking such detailed questions about our budget planning while having served on the Organising Committee of CSL 2026, for which the cheap early bird fee was 755 euros, the "lunches" were crappy sandwiches, and the "conference banquet" was held in a church hall corridor where the food was the leftover sandwiches from the lunch. I have never felt more cheated in my life...
Morgan Rogers (he/him) (May 28 2026 at 08:04):You're not the only one who felt that way! I would accept some responsibility if I had been in any way involved in organising the conference itself, but I was instead an organiser of an affiliated workshop whose price was also set (with very little transparency) by the colleagues organising the main conference.
Morgan Rogers (he/him) (May 28 2026 at 10:54):It feels bad that this is confrontational. I can't expect you to be able to change anything about the budget at this stage, and I kind of understand not wanting the decisions you've made to be put up for scrutiny by a wider audience, so instead of needling any further, I'll try naively to figure out how one arrives at an estimate of 600 per person.
I'll estimate (based on Oxford two years ago) that there are ~150 paying participants, plus 5 invited speakers, plus 15 local organisers.
Room hire: 6600 total for the week
Catering: Assuming lunch plus two coffee breaks, I'll estimate (28+6+6)5 per person, so 200170 for everyone
Travel costs of invited speakers: 700*5 (based on supposing that a return flight to Tallinn from Paris as searched today is a reasonable median price if they're mostly coming from within Europe/UK?)
Hotel costs of invited speakers: 600*5 (ballpark estimate from a quick search on Booking.com)
Conference dinner: 80*170 (big range possible here!)
That totals to 60700, so just over 400 per paying participant, of which over half is catering.
This was a naive estimate, of course, any of those numbers could be off by a factor of ~2. I could also be missing some costs such as publishing or underestimating how much it costs to procure coffee in Tallinn. I also don't know if there is any institution involved that expects to make revenue from the event that could inflate the cost.
Pawel Sobocinski (May 28 2026 at 13:13):Your numbers are close to what we expect -- in fact our total projected expenses are ~62k. Where we differ is the number of expected paying participants: we estimate ~80 payers based on number of accepted papers. The total number of participants is estimated at ~110: in addition to locals, there will also be students and tutors from the adjoint school who get a free ride.
Morgan Rogers (he/him) (May 28 2026 at 14:44):I hadn't taken into account the adjoint school at all, that accounts for the difference. Thanks Pawel. And I hope you managed to find better caterers than we had at CSL :upside_down:
Pawel Sobocinski (Jun 01 2026 at 13:07):We have around 3k euros to provide financial support to those attending ACT -- please fill out this form by June 15 https://docs.google.com/forms/d/e/1FAIpQLSd6nTlP6PLMXrLIge8F7Scz2lWK1iXe5WEIZScWt2HN_VeQFw/viewform?pli=1 (the link is also accessible via the website https://actconf2026.github.io/)
Cole Comfort (Jun 06 2026 at 10:41):Perhaps many of the people who submitted extended abstracts would not want the attached paper to be published on the website, or at least not indexed by google scholar.
Cole Comfort (Jun 09 2026 at 08:07):Does anyone else share my concern over the appallingly bad quality of one or more of the accepted papers? Is the steering committee taking any steps to prevent these submissions from being accepted from talks, or even worse, for publication?
Also, on a related note, it is unclear which papers, if any, have been accepted for a talk or publication under the "Teaching & Communication" track.
Pawel Sobocinski (Jun 09 2026 at 08:13):@Cole Which ones are the appallingly bad quality ones?
John Baez (Jun 09 2026 at 08:34):The steering committee is far from the first line of defense against bad papers. First it's the program committee, of course, since they review papers. If that fails then it's the job of the program committee chairs to deal with things: they are @Geoff Cruttwell and @Priyaa Varshinee. If they fail then the conference organizers (@Pawel Sobocinski, @Priyaa Varshinee, Sofia Taskova and Kristiya Ainen) should step in. Only if they fail - but Pawel just stepped in! - does the steering committee have to do something.
The steering committee's main job is to plan new ACT conferences - for example right now we are planning ACT2028. We also get involved in deciding the overall structure of ACT conferences. We have never been involved in reviewing papers. It is, however, our job to save the day when nobody else does.
I would urge @Cole Comfort to tell @Pawel Sobocinski privately which papers he thinks are appallingly bad. If you discuss this publicly here, the authors of these papers will inevitably read it and want to join the conversation.
Nathanael Arkor (Jun 09 2026 at 08:39):If you look through the accepted papers and talks in the order they appear on the website, you will almost immediately come across one that I am certain is LLM-generated.
John Baez (Jun 09 2026 at 08:46):Can you whisper in my ear (in a direct message) which paper you are certain is LLM-generated or LLM-assisted? I have thoughts on this....
I forget if the conference has an official policy about LLM use.
Pawel Sobocinski (Jun 09 2026 at 08:47):None of the people in this thread were on the PC, took part in deliberations, and were therefore jointly responsible for the decisions. I think it's unfair that we cast judgement on their hard work, which is done for free and for the good of the community.
John Baez (Jun 09 2026 at 08:54):I agree with that. Of course people will cast judgement on the program committee's work, and they will complain about it. People are like that. But any sort of official action should go something like this: people should complain privately to the program committee chairs and/or conference organizers and/or steering committee, providing details, and those bodies should discuss what to do. The most likely result will be to change procedures for the next conference, to improve things.
Nathanael Arkor (Jun 09 2026 at 08:58):Several of the people in this thread are authors who have accepted papers and talks at ACT. I think it is entirely fair for them to complain about the quality of accepted submissions at ACT, because the quality of the other submissions reflects on their own.
Nathanael Arkor (Jun 09 2026 at 08:58):(Of course, I also agree with @John Baez about the procedure in this case.)
Pawel Sobocinski (Jun 09 2026 at 09:18):Sure, whinging is easy.
Nathanael Arkor (Jun 09 2026 at 09:25):Dismissing legitimate complaints by describing them as "whinging" is also easy :slight_smile:
Nathanael Arkor (Jun 09 2026 at 09:32):In any case, I would suggest anyone who has concerns to raise them with the PC. They are more likely to take note of many voices than one.
Pawel Sobocinski (Jun 09 2026 at 09:39):That's a more productive approach, but still I would really emphasise that the work of the PC needs to be respected and valued and not second guessed at every opportunity. The decisions have been made. I am sure the PC took its role seriously and did their best with the finite amount of time and resources that they had to work with. No human process is infallible, and I'm sure mistakes were made, like they do with any human activity. I think the better option would be to write to the SC with any particular pointers/ideas on how future PC meetings could be run better and any suboptimal decisions avoided.
Pawel Sobocinski (Jun 09 2026 at 09:39):Which is to say, I agree with @John Baez ;)
Cole Comfort (Jun 09 2026 at 09:49):Pawel Sobocinski said:
None of the people in this thread were on the PC, took part in deliberations, and were therefore jointly responsible for the decisions. I think it's unfair that we cast judgement on their hard work, which is done for free and for the good of the community.
I cast judgement on the judgement of some of the PC members, despite not knowing who they are. Not all reviews are the result of hard work. Moreover, just as for papers, working hard on something doesn't necessarily make it good.
Cole Comfort (Jun 09 2026 at 09:52):Over the past few years there have been several accepted papers which me and many of my other colleagues have judged to be crackpottery. To just ignore this makes category theory look unserious, and can result in crackpots being promoted to PC members, perpetuating the cycle.
John Baez (Jun 09 2026 at 10:02):I just checked and remembered that the Steering Committee has not settled on an AI policy, though we discussed it. How are other, bigger conferences dealing with this issue?
Pawel Sobocinski (Jun 09 2026 at 10:09):The ACM very recently updated their policy on authorship, which I think is pretty good. https://www.acm.org/publications/policies/new-acm-policy-on-authorship
John Baez (Jun 09 2026 at 10:12):Thanks! I'll quote a bit, since people may not click the link:
Rather than attempt to limit the use of Artificial Intelligence (AI) to conduct research or report on the results of that research by placing expectations on authors to disclose all uses of large language models in their Works, this updated Policy attempts to set clear expectations for their responsible use, as follows:
- When using Artificial Intelligence to conduct research, including the design and methodology of the research project, creation and selection of data sources, designing experiments, generation and collection of data, coding, implementing models, running simulations, data analysis, testing, validating results, deploying software, archiving data and code for reproducibility, or any other aspects of the research lifecycle that are directly relevant to the conclusions of the research underlying the Work, the specific use(s) of AI tools must be described in detail in the methods section of the Work. This includes the creation of artifacts that are directly relevant to the conclusions of the research, such as code, datasets, and charts or figures that rely on the AI tools.
- When using Artificial Intelligence to assist with writing an ACM submission, ACM no longer requires the disclosure of information regarding the use of AI (as distinct from AI used in the conduct of the research itself, addressed in item 1 above).
All named authors on an ACM submission will be held responsible and accountable for any problematic content contained in the submission regardless of the source of that problematic content:
- In the event content integrity issues stemming from the use of AI during authorship are identified prior to publication or posting in the ACM Digital Library, ACM reserves the right to reject submissions in their entirety and impose additional penalties.
- In the event content integrity issues stemming from the use of AI during authorship are identified after publication or posting in the ACM Digital Library, ACM reserves the right to retract the published Work in its entirety.
A retraction notice will be published on the citation page of the published Work, indicating the Work has been retracted because of integrity issues identified after publication, including the inclusion of fraudulent material. ACM may or may not include any reference to the use of Artificial Intelligence in the retraction notice.
John Baez (Jun 09 2026 at 10:14):It's interesting that the ACM no longer requires the disclosure of information regarding the use of AI for writing an ACM submission, "as distinct from AI used in the conduct of the research itself". In mathematics I find it pretty hard to separate the research from the process of writing.
Jules Hedges (Jun 09 2026 at 10:20):For what it's worth - and I kept this to myself while reviewing was going on - in the past I have always approached reviewing on the assumption that the authors probably know what they're talking about, with a personal policy that I prefer to "accept first and ask questions later". This year for the first time I approached reviewing adversarially, expecting about half of the papers assigned to me would be fake (the reality was not as bad as I had feared). I can imagine a lot of people on the PC just aren't aware of how bad things have got out there
Mike Shulman (Jun 09 2026 at 15:13):Agreed @Jules Hedges . I am also in the process of adjusting my approach and expectations as a reviewer and PC member. There were several submissions I was assigned to this year that had some disagreement in the original reviews that was due, I think, to some PC members being adversarially AI-suspicious and others more traditionally generous. I think I was on both sides of that divide for different submissions. I could easily see it happening randomly that some other submission got assigned all-generous reviewers and slipped by.
With that said, some additional guidance for the PC on this issue might not be amiss in the future.
Mario Román (Jun 09 2026 at 16:20):John Baez said:
The steering committee is far from the first line of defense against bad papers. First it's the program committee, of course, since they review papers. If that fails then it's the job of the program committee chairs to deal with things: they are Geoff Cruttwell and Priyaa Varshinee. If they fail then the conference organizers (Pawel Sobocinski, Priyaa Varshinee, Sofia Taskova and Kristiya Ainen) should step in. Only if they fail - but Pawel just stepped in! - does the steering committee have to do something.
The steering committee's main job is to plan new ACT conferences - for example right now we are planning ACT2028. We also get involved in deciding the overall structure of ACT conferences. We have never been involved in reviewing papers. It is, however, our job to save the day when nobody else does.
I would urge Cole Comfort to tell Pawel Sobocinski privately which papers he thinks are appallingly bad. If you discuss this publicly here, the authors of these papers will inevitably read it and want to join the conversation.
Kristi, Sofiya, and Pawel are not in any scientific committee for ACT26 as far as I know (local organizers do not even need to be scientists). I am sad to see that you try to point to them instead of assuming responsibility. If the PC chairs "fail", then it becomes the responsibility of the Steering.
Matteo Capucci (he/him) (Jun 10 2026 at 07:45):Just like with the Teaching & Communication track discussion, I think the real culprit here is transparency and communication. I expect the committee members to listen to concerns (which seem well-founded) and publicly advertise how they plan to act on them. I also expect community members to be kind when voicing such concerns---this is all being done on a voluntary basis, so we could do without the vitriol. John outlined a good procedure for doing so.
From what I could see as a PC member, it seems there was an unfortunate (if preventable, IMO) alignment of slips that meant not enough attention was paid to a certain submission. As Jules eloquently put it, we cannot afford anymore to defer to the human on the other side of the paper to 'make sense'. Like many other social systems nowadays, the reviewing system is also showing some cracks under the stress of AI.
I believe we need to have a discussion (maybe in Tallinn) about what changes to the revision process should be made to prevent incidents like this in the future.
Also, as an author and PC member, I expect the submission to be rejected now (honestly, I don't care about AI-generated or not, the point is the paper does not seem to make sense to anyone here, which means it's not of good quality).
John Baez (Jun 10 2026 at 17:09):Mario Román said:
Kristi, Sofiya, and Pawel are not in any scientific committee for ACT26. If the PC chairs "fail", it becomes the responsibility of the Steering, not of Kristi, Sofiya, or Pawel.
Okay, that makes sense. Regardless, the Steering Committee is now looking into the issue.