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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJul 5th 2012

    started an entry Planck’s constant with a remark on its meaning from the point of view of geometric quantization (and nothing else, so far).

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeMar 29th 2014

    Added Planck constant – Basic definition, just for fun. (And also since it’s a point rarely made explicit, simple as it is.)

    • CommentRowNumber3.
    • CommentAuthorTodd_Trimble
    • CommentTimeMar 29th 2014
    • (edited Mar 30th 2014)

    Am a little surprised that nothing (or barely anything) was said about the dimension of hh as a physical unit, as measured in (kg)m 2s 1(kg)m^2 s^{-1} or whatever. Is that considered too low-level?

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeMar 30th 2014

    It’s not too low level, no. Please add it if you have energy.

    • CommentRowNumber5.
    • CommentAuthorTodd_Trimble
    • CommentTimeApr 1st 2014

    Well, I had the time and energy (measured in joule-seconds?) to put in a little something about Planck’s constant as a physical constant, but it might be considered embarrassingly low-level. In which case, please feel free to jazz it up to suit taste.

    • CommentRowNumber6.
    • CommentAuthorThomas Holder
    • CommentTimeApr 1st 2014

    Mentioning the Planck scale there would give a peg to hang on a funny observation of John L. Bell in some version of ch.1. of his primer of infinitesimal analysis, namely that the infinitesimal neighborhood of 0 is akin to the Planck scale in that there the order-theoretic structure of the smooth line breaks down. I wonder whether more could be made of this observation. Unfortunately, I can’t give a more precise reference here, because I have this version in electronic form only, and it isn’t contained in the first print edition nor can I find a corresponding text on his homepage.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeApr 1st 2014

    Thanks, Todd.

    I have moved your addition up to the top. Then I added an Idea-section which points to the various subsections.

    Will have to create an entry physical unit now.

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJan 26th 2019
    • (edited Jan 26th 2019)

    added a brief History-comment just so as to link back to entries such a black body radiation and ultraviolet catastrophe

    diff, v15, current

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