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  1. Add a reference for string diagrams in closed monoidal categories


    diff, v42, current

    • CommentRowNumber2.
    • CommentAuthora_delpeuch
    • CommentTimeJul 28th 2019
    Wow, there is not a single string diagram shown on the page "string diagram".
    How can this page be useful to anyone who does not already know about these diagrams?
    Surely it cannot be accidental - am I missing something here? I guess I will try to add some myself and see what happens…
    • CommentRowNumber3.
    • CommentAuthorMike Shulman
    • CommentTimeJul 28th 2019

    I expect this is because it’s only very recently that functionality like tikz was available on the nlab for drawing string diagrams. Before that they would have had to be included images or svg, and probably no one wanted to put in the effort.

    • CommentRowNumber4.
    • CommentAuthorDavid_Corfield
    • CommentTimeJul 29th 2019
    • (edited Jul 29th 2019)

    Wow, why is someone surprised that a wiki constructed by a very few guys in their spare time doesn’t have every desirable feature?

    The only “accidental” thing is that there are so few people who can be bothered to contribute.

    • CommentRowNumber5.
    • CommentAuthora_delpeuch
    • CommentTimeJul 31st 2019
    • (edited Jul 31st 2019)
    Sorry, I did not mean to offend the previous contributors… but for me it is a bit symptomatic of the overall style of the house.

    If my additions of diagrams are welcome then I will keep doing that. I just wanted to double check that I had not missed some reason why diagrams had been left out.
    • CommentRowNumber6.
    • CommentAuthorDavid_Corfield
    • CommentTimeJul 31st 2019

    No, there is no reason that diagrams have been left out. It’s just a question of the changing interests and energy levels of the very few people here, and the functionality available.

    I can’t imagine what you took a lack of string diagrams to be a symptom of. Mike Shulman has publications using them, such as Traces in symmetric monoidal categories. So do I for that matter, Ch. 10 of my book.

    I see you added one at double category. Keep it up. Plenty of opportunities obviously on this page, string diagram.

    • CommentRowNumber7.
    • CommentAuthorTodd_Trimble
    • CommentTimeJul 31st 2019

    “Style of the house.” Sigh.

    There is no house style. Each contributor has his/her own style of writing. (There are a few conventions, but they do not dictate style.)

    • CommentRowNumber8.
    • CommentAuthorMike Shulman
    • CommentTimeJul 31st 2019

    I don’t think we should be surprised that people think there is a “house style”, or that decisions about what or what not to include were made in some centralized or intentional way, or that by adding something to scratch their own itch they might be violating some norms or expectations. The idea of a truly decentralized wiki is still alien to the way people are used to thinking about the way things are written and created. Most people’s experience with wikis is limited to wikipedia, which is nowadays much more centralized and controlled than we are, and probably looks even more so than it is to the casual reader.

    (I’m not necessarily claiming that any of this applies to any particular person such as a_delpeuch, just responding to the general feeling of frustration with this misconception that David and Todd are expressing — which I do share, but I’m more or less resigned to it by now.)

    • CommentRowNumber9.
    • CommentAuthorDavid_Corfield
    • CommentTimeJul 31st 2019
    • (edited Jul 31st 2019)

    Some of my annoyance is a carry-over from reading some ill-informed comments on Twitter. Some people seem to think that unless an entry is swimming in (,1)(\infty, 1)-tags that we don’t want to know. No doubt it would be better for me not to read this, but it has made me aware that there are people under the banner of ’Applied Category Theory’ who have the impression that it will require a radical shift to have their ideas represented here.

    While some scepticism was expressed about the ACT-movement in the corresponding discussion, the one explicitly anti-ACT view aired on the nForum that I know about was given anonymously by ’Guest’ at game theory.

    Ah, now I see that a_delpeuch participated in the discussion Applied Category Theory on the nLab. The idea that we’re ultra-abstract and unapplied is in the air.

    Can’t people just come along with a modicum of humility, find out a little bit about how things work around here, and then get on with providing some content?

    • CommentRowNumber10.
    • CommentAuthorTodd_Trimble
    • CommentTimeJul 31st 2019

    I’m tempted to start writing “Myths About the nLab”, but I’ll hold off on that.

    IIRC, Urs said something in the other thread (linked to by David C in the last comment) about not letting all these meta-thoughts about the nLab get in the way. I agree. There’s a lot to be done, so if you have something useful you’d like to add, please just go ahead. Personally, I’m really glad that a_delpeuch is putting in string diagrams. We need them, and needed them. The lack had nothing to do with any supposed philosophical or stylistic opposition to them.

    • CommentRowNumber11.
    • CommentAuthorDavid_Corfield
    • CommentTimeAug 1st 2019

    All very odd when you consider that of the authors of the last three comments, two have done important mathematical/logical work with string diagrams and the other has discussed their philosophical importance.

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