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    • CommentRowNumber1.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJul 5th 2024
    • (edited Jul 5th 2024)

    I’ve created this discussion following the recent posts in the discussion of fivebrane 6-group and since I have two more points that are unclear to me:

    • What about capitalization? Fivebrane group is capitalized and fivebrane 6-group is uncapitalized. According to HowTo, “page titles should be uncapitalized, except for words that are always capitalized.” As far as I know, spin and string groups are always uncapitalized as text, while Fivebrane and Ninebrane groups are always capitalized as text. (With all of them capitalized in formulas of course.)
    • What about hyphens? There are examples, where one seems to be missing, for example Fréchet Lie group and Conner-Floyd Chern class.
    • What about superscripts? Unicode provides letters in superscript, which for example enables to create a page titled spinᶜ while the current page is titled spin^c. Another example is MSpin^c.
    • CommentRowNumber2.
    • CommentAuthorDavidRoberts
    • CommentTimeJul 5th 2024

    I personally have moved over to writing Fréchet–Lie group (with an en-dash), but I don’t know if this is standard. “Fréchet” as an adjective like in “Fréchet manifold” or “Fréchet space” etc doesn’t have a any type of dash/hyphen.

    I guess there’s some kind of unspoken convention around a new type of object whose name is “from a person” when it already has such a name. I don’t know if it’s consistent. There are things like Grothendieck–Riemann–Roch, which doesn’t seem like it is ever “Grothendieck Riemann-Roch” (but people do say “Grothendieck’s Riemann-Roch theorem”, but that clearly doesn’t work for objects like infinite-dimensional Lie groups).

    This to some extent highlights the known issues with using people’s names to name types of objects, that’s not a nLab problem, and a much harder discussion to resolve.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJul 5th 2024
    • (edited Jul 5th 2024)
    • On a gut level I find that “Spin group” is more pleasant to the eye than “spin group”. But nLab convention is that only names be capitalized, usually understood as: names of people and titles of texts, not names of mathematical concepts. Therefore it should probably be lower case, and with it “fivebrane group” etc.

    • On the hyphens I have no opinion. But the two instances you quote make some sense in themselves, in that Conner & Floyd were coauthors of each other, but not of Chern.

    • On the superscipts: While I was the one who created the entries titled “spin^c” and “MSpin^c”, I never liked their look, just didn’t know what else to do. Your fix using unicode seems clearly superior. I will take the liberty of implementing that for these entries right now.

    • CommentRowNumber4.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJul 5th 2024
    • (edited Jul 5th 2024)

    Concerning Conner-Floyd Chern class: If that decides about hyphens, what about articles like Einstein-Yang-Mills-Dirac-Higgs theory?

    I’m planning to create articles for “Banach Lie group/Banach-Lie group” and “Hilbert Lie group/Hilbert-Lie group”. Which title should I use?

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJul 5th 2024

    I won’t claim that it “decides” it, just observed that it “makes some sense”.

    Just on a case-by-case basis:

    I feel that “Chern class” is a stand-alone term. Hence if X, Y & Z come and define a variant Chern class it derserves to be called “X-Y-Z Chern class” instead of X-Y-Z-Chern class.

    This seems different for “Einstein-Yang-Mills-Dirac-Higgs theory”. If anything, then the pair Yang & Mills here is special, since these are like Conner & Floyd above in that their contribution is through a joint authorship. So on pure logic it would make sense to write “Einstein Yang-Mills Dirac Higgs theory”, if it were not for the fact that this seems to have too many whitespaces to be pleasantly readable.

    In conclusion, I doubt we can find a general rule here that is always applicable. We need to see on a case-by-case basis what works well.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeJul 5th 2024

    Regarding Banach Lie groups and Hilbert Lie group, I might tend to write them without hyphen.

    BUT in any case, none of this should delay you in creating an entry! Just create it with any name and b sure to add all reasonable redirects, then no harm will be caused.

  1. No problem, “Banach Lie group” and “Hilbert Lie group” it is (or will be).

    • CommentRowNumber8.
    • CommentAuthorDavidRoberts
    • CommentTimeJul 8th 2024
    • (edited Jul 8th 2024)

    If that’s the case, then to close a question in the original post, it will also be Fréchet Lie group, no hyphen.

    • CommentRowNumber9.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJul 17th 2024
    • (edited Jul 17th 2024)

    Today I realized, that not only spinᶜ and spinʰ can be updated using unicode superscripts but also G2, F4, E6, E7 and E8 using unicode subscripts. There are not many titles needing to be fixed (ten for G2, three for E8 and only the page itself for F4, E6 and E7) but it will probably be necessary to go through hundreds of articles to check if links need to be fixed or if the search algorithm just picked up something else entirely, for example an URL (which is for example the case for Lucy Yang where “yang257” appears). I could start doing this, but before making so many little changes including changing titles, I wanted to ask if that’s okay first?

  2. I’ve also noticed, when searching through some obvious pages where G2 might need to be fixed, that there are three different conventions for the titles of articles about Chern-Simons theory in a particular dimension:

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeJul 17th 2024

    These are good points.

    Regarding the subscripts: Sure, it would be good to make this change. Adjusting the link texts is not critical, as long as the old titles remain as redirects.

    Regarding CS-theory: For Yang-Mills theories and gravity theories I eventually settled on the format “D=D=\cdots theory”. May be best to adopt this for all CS-theory entries, too.

    Thanks for looking into these matters!

    • CommentRowNumber12.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJul 17th 2024
    • (edited Jul 17th 2024)

    Always happy to contribute! When editing U-duality – table, I’ve noticed that some titles of articles about supergravity also need to be changed:

    Since redirects exists, I’ve already changed the links in the table.

    • CommentRowNumber13.
    • CommentAuthorSamuel Adrian Antz
    • CommentTimeJul 17th 2024
    • (edited Jul 17th 2024)

    All titles of pages about exceptional Lie groups or Chern-Simons theory have been changed so far. I will soon continue to check links and articles, where changes in the content are necessary, as well as changing titles where necessary. How about adapting the “D=n” convention to all titles, for example also including:

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeJul 17th 2024

    Thanks for all this!

    Yes, sure, let’s harmonize also the titles of the TQFT entries.

  3. You’re welcome! Other titles are now also changed, but there’s a problem. When changing the title of 4d TQFT to D=4 TQFT, the former page was somehow created again with the exact same content and should be deleted. (The edit logs were moved to D=4 TQFT.)

    I’ve also noticed when trying to move 10d supergravity, that another article called D=10 supergravity already exists. Both have different content, but only contain links. How about merging the former into the latter?

    Then there’s another page existing twice, which is Shiing-Shen Chern/Shiing-shen Chern.

  4. Yesterday, I’ve replaced “G2” by “G₂” in all articles I could find, roughly 100-150 of the roughly 400 articles the search algorithm gives out. Whenever present, I’ve also replaced indices of other exeptional Lie groups and the nD with the D=n convention.

    (Something, that was a bit strange, was that dozen of articles were currently edited by “Anonymous”. Once, I’ve encountered roughly ten such articles in a row.)

    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeJul 20th 2024
    • (edited Jul 20th 2024)

    Thanks again for all your work!

    Interesting that you mention this issue with entries claiming that they are being edited by “Anonymous”.

    I get that a lot, too, since the early days of the nLab, but you are the first one to confirm seeing the same effect.

    Back in the old days, when the default user name still was “Anonymous Coward”, I once tried to contact them by an nForum message asking them please to stay away from editing just those entries that I was working on, until I am done – but I never received a reply. Similarly, when then instead starting to regularly break the alleged lock, I never ran into an edit conflict in these situations.

    Therefore I expect that these Anonymous lock-messages are a strange software bug instead of actual users causing them. This is all the more plausible now that we have blocked the user name “Anonymous” from submitting edits! (Of course they can technically still block entries, but it seems all the more unlikely that a user busily locks dozens of entries without ever sumitting an actual edit.)

    It seems hard to give a useful bug report for this phenomenon, but maybe we should try.

  5. So, after a long pause to write my Master thesis, I’m happy to continue a bit of work here! I’ve written five new articles about Yang-Mills theory, three of which contain “equation” in its title. But how about “equations” since a single equation can contain more? After looking through some entires, it seems that only the first convention is used here for such examples, for example Dirac equation and Bogomolny equation.

    • CommentRowNumber19.
    • CommentAuthorUrs
    • CommentTimeOct 31st 2024
    • (edited Oct 31st 2024)

    Sounds good.

    If a subject name is more natural in plural form – such as “equations of motion” – then let’s use that!

    • CommentRowNumber20.
    • CommentAuthorSamuel Adrian Antz
    • CommentTime1 day ago
    • (edited 22 hours ago)

    The edit yesterday on E₁₁ reminded me: I noticed a few other articles, which could need an Unicode treatment:

    Is it okay if I change it again? I’m asking, because I noticed an important point, unfortnutely only a few weeks after all my previous edits: When the title is changed, for example from containing “G2” to containing “G₂”, the article stops showing up when searching for “G2”. A solution could be to create an article with the original title and then add only “See XXXX” as content. (For example like on Ek-Algebras.) With all the titles I changed, that would require maybe two to three dozen such articles.

    Is that an option? Is there another possibility? Is this even a problem at all?

    And how about unifying Ek-Algebras and En-algebra in the process? Singular or plural and small or large?

    I haven’t yet found an unicode symbol for ∞ in superscript, which would be useful here:

    This also concludes all articles currently having ^ in their title.

    • CommentRowNumber21.
    • CommentAuthorUrs
    • CommentTime15 hours ago

    I don’t have a strong opinion on this.

    A couple of thoughts (inconclusive):

    As for the search: I never use the built-in search function, instead I use Google with flag site:ncatlab.org.

    But if the built-in search is intentionally used for more pedantic keyword matching, then maybe it’s a good thing that it discriminates between “G2” and “G 2G_2”. (Is it at all possible to enter the latter into the built-in search box?)

    On my phone the new titles like “E 11E_{11}” don’t display properly – the subscript appears as two boxes. Of course this must mean that it’s my fault not to have installed necessary fonts, but then the same probably applies to other users.