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Matteo Capucci (he/him) (Nov 13 2023 at 09:00):Does anyone know how to quickly find the DOI of a TAC paper? It's not on the abstract page
Nathanael Arkor (Nov 13 2023 at 09:02):TAC papers don't currently have DOIs. I believe @Chris Grossack (they/them) was looking into DOI assignment for TAC papers?
John Baez (Nov 13 2023 at 09:43):Yes, Chris was talking to the head editor of TAC, Geoff Crutwell, about that. I believe it turned out that getting DOIs for existing papers would require a nontrivial amount of work - doing something to each one of those papers. But @Chris Grossack (they/them) knows the details!
John Baez (Nov 13 2023 at 09:44):Maybe it's a bit easier and still useful to get DOIs for all new TAC papers?
David Michael Roberts (Nov 13 2023 at 09:58):Just getting new a doi for new papers would be a start. The backlog can be slowly worked on over years, if need be.
Jules Hedges (Nov 13 2023 at 12:18):They also cost money, no? Each one is very cheap but they probably add up to quite a bit
Chris Grossack (they/them) (Nov 13 2023 at 15:18):I'll throw the alerts back at @John Baez and say he was willing to find funding (it's actually way less expensive than you think, and I'm sure John has grants for such things)
Chris Grossack (they/them) (Nov 13 2023 at 15:19):It's been a while since we talked about this (steering a ship the size of TAC is pretty slow) but I'm still happy to do the work
Chris Grossack (they/them) (Nov 13 2023 at 15:20):Plus I'm extremely confident that if there's some tedious task we have to do for each paper in the backlog that there will be other people in the zulip willing to help out with 5 or 10 at a time (actually, can you react to this if you would be open to helping with this project?)
Chris Grossack (they/them) (Nov 13 2023 at 15:23):It's been a while since I looked into it, but the most tedious aspect (which can't be automated with code scraping the TAC website) is adding DOI cross references for the bibliographies of each TAC paper.
I also, importantly, don't know if we actually need to do that. We definitely need to do it going forward, but the website is kind of confusing regarding the backlog. Once TAC gives me a tentative go ahead I'll contact the DOI people and double check exactly what the requirements are
Nathanael Arkor (Nov 13 2023 at 15:56):We definitely need to do it going forward
What precisely is the requirement? For instance, arXiv assigns DOIs for each preprint, but does not require preprints to include DOIs in their bibliographies.
John Baez (Nov 13 2023 at 16:02):Chris Grossack (they/them) said:
I'll throw the alerts back at John Baez and say he was willing to find funding (it's actually way less expensive than you think, and I'm sure John has grants for such things)
No, I don't have any grants for anything! I've generally avoided the whole grant system, though this will have to change with the new Fields Institute project. I was just willing to spend my own money on this - given the figures I heard, which by now I completely forget. How much do DOIs cost, again?
Chris Grossack (they/them) (Nov 13 2023 at 16:12):I'll be honest, I don't remember either, haha. I'm about to leave the house, but I'll either find our old discussion or redo the estimate later today
Graham Manuell (Nov 13 2023 at 18:37):I think for a single DOI it's around $1, but I imagine if you do it in bulk there are substantial savings.
David Michael Roberts (Nov 13 2023 at 21:32):Chris Grossack (they/them) said:
It's been a while since I looked into it, but the most tedious aspect (which can't be automated with code scraping the TAC website) is adding DOI cross references for the bibliographies of each TAC paper.
I also, importantly, don't know if we actually need to do that. We definitely need to do it going forward, but the website is kind of confusing regarding the backlog.
There's no way articles all need to have DOIs added to the actual pdfs/etc, since this didn't happen for eg Springer's enormous back catalogue of scanned papers.
David Michael Roberts (Nov 13 2023 at 21:33):I think talking to the Compositionality people would be a good idea, as they have DOIs
John Baez (Nov 13 2023 at 22:53):I'm one of the Compositionality people, but the right people to talk to are @Nina Otter (formerly on the journal, who would know how to start getting DOIs) and @Jade Master (who would at least know who makes this happen now).
The big difference is that Compositionality got DOIs for its papers from the very start. Getting DOIs for old papers is a bit more mysterious, at least to me, and the Compositionality people wouldn't know about that.
David Michael Roberts (Nov 14 2023 at 05:43):I just mean getting DOIs for papers going forward, not for the historical backlog, which I am theorising is a completely different matter.
John Baez (Nov 14 2023 at 07:14):Okay, we agree. Anyway, those are two relevant people at Compositionality.
Jade Master (Nov 14 2023 at 10:30):Hello :wave: @John Baez, @Chris Grossack (they/them), @David Michael Roberts . The DOIs for Compositionality are handled by a wordpress plugin so TAC will need to use a different system. I will point you to the CrossRef documentation which will hopefully have answers to your questions. In particular, here is the fees page. (as you can see it is $275 a year + $1 per article).
Jade Master (Nov 14 2023 at 10:34):I should also mention that we are planning a move to Episciences soon. Episciences will handle the DOI registration for us (including the fees!) so if TAC is willing to give up their old website and modernize a little then Episciences could be a very good option for them as well.
Nathanael Arkor (Nov 14 2023 at 10:49):if TAC is willing to give up their old website and modernize a little
Episciences is a platform for overlay journals, which have advantages and disadvantages compared to traditional journals, so I don't think it's reasonable to describe such a change as "modernising" (especially "a little").
Jade Master (Nov 14 2023 at 10:54):True that it's not an overlay but I'd be willing to bet that most of the articles on TAC are already also on arxiv.
Jade Master (Nov 14 2023 at 10:57):I'm not involved with TAC at all, just trying to give helpful suggestions. I'm not saying that they should switch to Episciences...just something to consider. We have found that it will reduce the work needed to run Compositionality by a lot.
David Michael Roberts (Nov 14 2023 at 11:10):Actually, Scholastica is also a good OA platform, if TAC would go for a new infrastructure.
Jade Master (Nov 14 2023 at 12:10):Scholastica is a good option, but would come with another set of fees unfortunately.
Morgan Rogers (he/him) (Dec 08 2023 at 08:21):Is TAC down?
Bryce Clarke (Dec 08 2023 at 08:25):Morgan Rogers (he/him) said:
Is TAC down?
It is working fine for me on the usual link: http://www.tac.mta.ca/tac/
Graham Manuell (Dec 08 2023 at 09:14):I can access it at the moment, but in the past month it's been down for me more often than it's been up.
Morgan Rogers (he/him) (Dec 08 2023 at 09:28):Alright, I can access it again now, thanks for checking :)
John Baez (Dec 08 2023 at 09:30):If someone sees that TAC is down, they can email the editor, Geoffrey Cruttwell, at
To avoid flooding him with emails, you could mention here that you've done it.
John Baez (Dec 08 2023 at 09:31):We should not think of the "old" category theorists who run TAC, the annual CT conference, the nLab etc. as inaccessible gods.
Graham Manuell (Dec 08 2023 at 11:04):For the times it's down you can also always find the papers on the Internet Archive.
John Baez (Dec 08 2023 at 18:23):Are all TAC papers placed there?
Graham Manuell (Dec 08 2023 at 19:14):Every one I've checked at least, so it seems the site is crawled reasonably regularly.