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    • CommentRowNumber1.
    • CommentAuthorTobyBartels
    • CommentTimeMay 31st 2010

    An anonymous coward put something blank (or possibly some spam that somebody else blanked within half an hour) at Hausdorff dimension, so I put in a stub.

    • CommentRowNumber2.
    • CommentAuthorTobyBartels
    • CommentTimeMay 31st 2010
    • (edited May 31st 2010)

    Also a stub at Lebesgue measure, which has many incoming links.

    • CommentRowNumber3.
    • CommentAuthorIan_Durham
    • CommentTimeMay 31st 2010

    Again, I could fill this in some more, but I’m worried it won’t be from the right POV. I don’t want to make more work for others, but I’d like to contribute more than just quantum stuff. Any thoughts?

    • CommentRowNumber4.
    • CommentAuthorEric
    • CommentTimeMay 31st 2010

    @Ian #3: That kind of thing is a perfect example of what the nForum is good for. If you have some ideas, test them out here. The nLab is not necessarily the best testing ground. Once something is fairly polished here, it is a simple matter of copying and pasting the source to the nLab. in fact, someone else may even do the copying and pasting.

    • CommentRowNumber5.
    • CommentAuthorTobyBartels
    • CommentTimeMay 31st 2010

    I think that it’s reasonable to fill in the basics of the standard material, as you are now doing. The things that I might caution against are:

    • excessive details of standard material that is available in many other places, which is more pointless than harmful but could also be distracting;
    • unusual interpretations that aren’t grounded in the nPOV, which I think may have been what caused trouble in the past (^_^).

    There is stuff that I’ve been wanting to put there, but I haven’t gotten around to it yet; I finally created the page anyway because I got tired of seeing links to it. For example:

    • a careful definition that is both constructively valid and classically standard (so that it is clear that this can be done, as it can be);
    • characterisations by more or less abstract nonsense (such as the one that I wrote in the stub that I created, or Eric’s suggestion that there is a universal property in the Carathéodory extension theorem, which I’m sure there is).

    So you can do that too if you want, or not.

    • CommentRowNumber6.
    • CommentAuthorIan_Durham
    • CommentTimeMay 31st 2010

    OK, thanks. I know my CTC entry was not of good quality, but there had been some complaints about my quantum entries (which were just standard from my POV) so I am still a bit fuzzy about what constitutes quality and what doesn’t (particularly in light of the fact that Eric liked my Lebesgue measure entry). But I’ll figure it out eventually.

    • CommentRowNumber7.
    • CommentAuthorEric
    • CommentTimeJun 1st 2010

    But I’ll figure it out eventually.

    I think Toby already explained it:

    • unusual interpretations that aren’t grounded in the nPOV, which I think may have been what caused trouble in the past (^_^)

    I’m pretty sure you would agree that you have certain opinions on certain areas of physics that are neither mainstream nor nPOV. There was no opinion expressed at Lebesgue measure so it seemed like a perfectly good nLab entry.

    It is probably even “ok” to express a non-mainstream non-nPOV opinion occasionally on the nLab, but it should be done carefully and clearly marked as such. These things can become magnets for crackpots. Probably best to avoid it.

    • CommentRowNumber8.
    • CommentAuthorIan_Durham
    • CommentTimeJun 1st 2010

    Right, but Urs and David specifically singled out some of my quantum entries (quantum channels I think?) and I never offered an opinion there. I simply stated it the way it is used. That’s the essence behind my confusion. But, like I said, I’ll figure it out eventually.

    It’s probably hard to believe, but I really have very few opinions about anything in physics other than the fact that it’s all a bunch of imperfect models designed to explain empirical data.

    • CommentRowNumber9.
    • CommentAuthorTodd_Trimble
    • CommentTimeJun 1st 2010

    I’ll grant that the Caratheodory extension theorem looks very much like a completion process, which of course can be understood universally.

    • CommentRowNumber10.
    • CommentAuthorEric
    • CommentTimeJun 1st 2010

    I’ll grant that the Caratheodory extension theorem looks very much like a completion process, which of course can be understood universally.

    Cool. So I am developing some nSense (or just 1Sense or sense) :)

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