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On April 7th, 2021, the muon $(g-2)$ collaboration published Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm, a result which made it to standard news, partly under headlines like Farewell to the Standard Model (German source: Abschied vom Standardmodell)

The following quote from phys.org nicely summarizes what it is in general about:

The experiment at Brookhaven indicated that g-2 differed from the theoretical prediction by a few parts per million. This miniscule difference hinted at the existence of unknown interactions between the muon and the magnetic field—interactions that could involve new particles or forces.

I am now wondering if there are theoretical studies which illuminate what concrete effects a $g-2 > 0$ would have on astronomy, as e.g. Dominik Stöckinger states (translation by me):

Some variants of supersymmetry, in which so-called superpartner particles also explain dark matter, are no longer tenable by this measurement.

Related

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    $\begingroup$ cool question! $\endgroup$
    – uhoh
    Apr 8 at 21:52
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    $\begingroup$ I was not sure how it would be perceived, glad that you like it. $\endgroup$
    – B--rian
    Apr 9 at 6:41
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This is unlikely to have any implications for astronomy. They may have seen an extremely small deviation from the predictions of the standard model. The result may actually have to do with technical issues in theoretical methods, not with any new physics: https://arxiv.org/abs/2002.12347 . Even if it does have implications for new physics, there is no reason to believe that it would have implications for astronomy. It could, for example, be an indication of the existence of a new unstable particle with a high mass, whereas dark matter needs to be made of stable particles.

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    $\begingroup$ I think that you've called this one wrong. "...there is no reason to believe that it would have implications for astronomy." The early universe (cosmologists are astronomers and get their information about it from observational astronomy) was very different than it is today, Higgs and other bosons had quite an important role I don't see how one can be so sure that a possible new particle wouldn't as well! $\endgroup$
    – uhoh
    Apr 8 at 22:54
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    $\begingroup$ See also Week 3: Thermal History of the Universe I don't normally down vote but this one is quickly reversible if you can either rigorously support "no reason to believe" using authoritative sources or more careful arguments, or adjust/relax it accordingly and sufficiently. Thanks! $\endgroup$
    – uhoh
    Apr 8 at 22:55

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