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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeNov 26th 2012

    recorded some recent surveys of the status of MOND at MOND

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeMar 15th 2017

    I have been expanding slightly (mostly references) at MOND and related entries, such as fuzzy dark matter and axion.

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeOct 23rd 2017
    • (edited Oct 23rd 2017)

    Added pointers to articles discussing the constraints on MOND phenomenology due to the recent multi-channel observation of merging neutron stars: here

    • CommentRowNumber4.
    • CommentAuthorDavid_Corfield
    • CommentTimeOct 23rd 2017

    That was quick, or have the authors of those articles had access to the results for longer?

    Are rival theories, such as axionic dark matter, left unscathed by such observations? Perhaps further work by LIGO is needed there, at least according to Black Hole Mergers and the QCD Axion at Advanced LIGO.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeOct 23rd 2017
    • (edited Oct 23rd 2017)

    At least for arXiv:1710.06168 the computations were done earlier, and now that the expected results came in, it’s easy to draw the conclusion. They write:

    More details on DM emulator theories and some of their predictions made for externally triggered GW searches [45] during the era of initial and enhanced LIGO can be found in our previous works [46–48]. Now that the first simultaneous observation of GWs and photons has occurred, we can carry out our proposed tests.

    I think it’s fair to say that, while interesting, it is not particularly hard to obtain these kinds of conclusions – after all this is not about excluding subtle effects, but excluding brutal modification of the basic laws of physics. But since these modifications keep being promoted, these constraints are nevertheless worth recording.

    further work by LIGO is needed there, at least according to Black Hole Mergers and the QCD Axion at Advanced LIGO

    Thanks for the pointer, I had not seen this. So that’s about using future versions of LIGO not just to constrain axion dark matter models, but to directly verify some versions of them. We’ll have to wait and see…

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeApr 13th 2018

    added snippet from Bekenstein 04, p. 9 which makes manifest that the proposed “TeVeS” theory making MOND a relativistic theory is itself just Einstein gravity coupled to a very peculiar matter sector (and necessarily “dark” if this is to be realistic).

    diff, v13, current

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeApr 13th 2018

    also added the pointer to van Dokkum 18 on an observation of a galaxy that does not in fact show the effect which MOND claims is universal

    diff, v13, current

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJul 2nd 2020

    added pointer to yesterday’s

    • Kris Pardo, David Spergel, What is the price of abandoning dark matter? Cosmological constraints on alternative gravity theories (arXiv:2007.00555)

    diff, v14, current

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