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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeNov 8th 2019

    starting a stub. Nothing here yet, but need to save.

    v1, current

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeNov 9th 2019
    • (edited Nov 9th 2019)

    added a graphics (here) illustrating how what one might call the “shape observables” on the fuzzy 2-sphere (the integrals “ S N 2(R 2k)\int_{S^2_N} (R^{2k})” for any choice of fixing the ordering ambiguity of the integrand) are encoded by chord diagrams, and are in fact 𝔰𝔩(2)\mathfrak{sl}(2)-weight system Vassiliev invariants.

    To give this a little bit of a home, I added a minimum of text around that, and in order to give that text a bit of a home I added some further text with basics on the definition of the fuzzy 2-sphere.

    diff, v3, current

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeNov 11th 2019

    am adding pointers on the fuzzy 3-sphere:

    The fuzzy 3-sphere was first discussed (in the context of D0-brane-systems) in

    Discussion in the context of M2-M5-brane bound states/E-strings:

    diff, v5, current

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeNov 23rd 2019

    added the original references on the fuzzy 4-sphere:

    diff, v8, current

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeNov 23rd 2019

    added references on the fuzzy 6-sphere and higher:

    diff, v8, current

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTime4 days ago

    replaced the previous graphics (showing the chord diagrams coresponding to the various shape observables on the fuzzy 2-sphere) by a slightly improved version (here). Also adjusted the text slightly, but there remains much room for improvement.

    diff, v9, current

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