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    • CommentRowNumber1.
    • CommentAuthorDavid_Corfield
    • CommentTimeOct 8th 2018

    K-cohomology is a strangely organised page with 5 sections identically named. There supposed to be some difference from K-theory

    • CommentRowNumber2.
    • CommentAuthorRichard Williamson
    • CommentTimeOct 8th 2018
    • (edited Oct 8th 2018)

    Hehe, this and G-theory are two of the stranger ones I’ve bumped into as ’exceptional cases’ when I am making technical updates! They look like some kind of private note-taking experiments some years ago, it seems by Urs. We should definitely tidy both up.

    • CommentRowNumber3.
    • CommentAuthorRichard Williamson
    • CommentTimeOct 8th 2018
    • (edited Oct 8th 2018)

    Actually can add two more here as well. Maybe there are more, if one clicks on the categories used on these pages. [Edit: yes, see here.]

    • CommentRowNumber4.
    • CommentAuthorRichard Williamson
    • CommentTimeOct 8th 2018
    • (edited Oct 8th 2018)

    As an aside, this is an example where use of categories is unexpectedly helpful. I occasionally wonder, as Ali also raised earlier for the HoTT wiki, whether we should make greater use of them. Obviously not label everything ’category theory’, but things like ’knot theory’ or even ’mathematical physics’ might be useful. Could even drill right down into things like ’initiality conjecture’.

    • CommentRowNumber5.
    • CommentAuthorAli Caglayan
    • CommentTimeOct 8th 2018
    • (edited Oct 8th 2018)

    It seems that Instiki already uses them more then we do.

    Here is the all pages page on their wiki

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeOct 8th 2018

    Thanks for the alert. I strongly doubt that I created this entry!

    I have no memory of having created this entry, I feel like I am seeing it the first time.

    Now it does happen that I forget what I wrote into some nnLab entry.

    But every single line of this page defies the style in which I usually write.

    In particular I feel sure that I never ever in my life wrote a string like category: World [private]. Not only can’t I make sense of what this should mean, but I am also on record as suggesting not to use that category:-functionality at all, except for people and references.

    In short, I feel sure that I didn’t create this entry. Even though I do see that it has my name on it. I find this scary.

    The same applies to the entry “G-theory”. What on earth is going on here?

    I have cleared both entries now.

    If you find more such entries, please let me know.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeOct 8th 2018

    Oh, I see, you had already pointed out that there are more such entries. I sure didn’t write these!!

    Let’s look at L-theory. What looks like it would be by me is the first four lines, up to the hrule. That’s the style in which I create stubs when I want links to work: One minimum line of Idea, one pointer to Wikipedia, end.

    But what follows below the hrule is certainly not by me. This is clearly somebody else’s style, and, most importantly, the style of somebody who is completely unfamiliar with the nnLab.

    • CommentRowNumber8.
    • CommentAuthorRichard Williamson
    • CommentTimeOct 8th 2018
    • (edited Oct 8th 2018)

    Yes, my impression was also that it was not you who created these entries. It could be a form of spam. There are some further entries of the same kind, linked to in #3. I can just delete them later.

    We have discussed before the possibility of an optional log in/use of password for nLab editing. That would prevent this kind of imitation attack (for those users who have switched on the logging in). Actually, it would be quite easy and quick to implement a simple version of this: please let me know if I should do so.

    [Cross-posted with #7.]

  1. Following this discussion, I have now manually removed the apparently ’generated’ content from Revision 1 of this page, to avoid it being associated to Urs’ name.

    • CommentRowNumber10.
    • CommentAuthorRichard Williamson
    • CommentTimeNov 6th 2020
    • (edited Nov 6th 2020)

    I have completely deleted the former page ’G-theory’ and its history, since the only content on the current page was the word ’empty’, after Urs cleared the apparently generated content in 2018.