MOND, and other gravitational theories for explaining dark matter phenomena in galaxies that reproduce the radial acceleration relations (RAR), accurately reproduce the dynamics of the SPARC galaxies, the largest catalog of observational data regarding galaxy rotation curves. See, e.g., Pengfei Li, Federico Lelli, Stacy McGaugh, James Schormbert, "Fitting the Radial Acceleration Relation to Individual SPARC Galaxies" arXiv (February 28, 2018).
But, none of the standard shaped dark matter particle halos does that, and "fuzzy dark matter" can't reproduce this result for a consistent set of fuzzy dark matter particle properties.
Stellar and gas kinematics of galaxies are a sensitive probe of the dark matter distribution in the halo. The popular fuzzy dark matter models predict the peculiar shape of density distribution in galaxies: specific dense core with sharp transition to the halo. Moreover, fuzzy dark matter predicts scaling relations between the dark matter particle mass and density parameters.
In this work, we use a Bayesian framework and several dark matter halo models to analyse the stellar kinematics of galaxies using the Spitzer Photometry and Accurate Rotation Curves database. We then employ a Bayesian model comparison to select the best halo density model.
We find that more than half of the galaxies prefer the fuzzy dark model against standard dark matter profiles (NFW, Burkert, and cored NFW). While this seems like a success for fuzzy dark matter, we also find that there is no single value for the particle mass that provides a good fit for all galaxies.
Mariia Khelashvili, Anton Rudakovskyi, Sabine Hossenfelder, "Dark matter profiles of SPARC galaxies: a challenge to fuzzy dark matter" arXiv:2207.14165 (July 28, 2022).
MOND doesn't work for galaxies clusters and gravitational lenses
Remember MOND is just a curve fit, not a full theory, not based on GR. How does Deur do on clusters and lenses?
MOND underestimates the effect in galaxy clusters, it doesn't completely fail. I also disagree with you re gravitational lenses.
Deur does well on clusters which he addresses via the geometry of the mass distributions in clusters leading to dimensional reduction through field self-interaction to stronger flux tubes between galaxies in clusters.
Deur is using standard GR so lensing is the same as GR.
OT: 22ka human footprints at White Sands, New Mexico, is now plausibly supported by 37ka mammoth butchery site: https://www.dailymail.co.uk/sciencetech/article-11070001/Humans-settled-North-America-17-000-years-EARLIER-previously-believed-study-finds.html
I agree that the 22ka human footprints are plausible.
I have serious doubts about the mammoth butchery site claim, since similar claims seemingly from hominins previously successfully attributed to animals in the past.
Dark matter from 12 billion years ago detected for the 1st time
By Robert Lea published 2 days ago
Scientists used a fossil relic left over from the Big Bang to perform the earliest detection of dark matter ever.
The telescope looked at the gravitational lensing of cosmic microwave background signals around a very old galaxy, which is essentially the same as what you do with a not so old galaxy (only its harder and requires a much better telescope to see), and doesn't actually do anything to distinguish between this phenomena being caused by a gravitational mechanism and being caused by a dark matter particle mechanism. The term "fossil relic" is a metaphor here not a statement that they actually directly observed one or more dark matter particles, they merely inferred it from gravitational lensing of CMB signals by the old galaxy.
LambdaCDM predicts that such an early galaxy should have a clumpy DM distribution. This inferred DM distribution was smooth just like lower z value galaxies are observed to have. So, the observation actually disfavors the paradigm in favor of models that produce recent type galaxies more quickly the LambdaCDM. Gravitational theories to explain DM phenomena generically make this prediction. Of course, it is also possible that some DM model other than the collisionless cold dark matter of the LambdaCDM also results in earlier galaxy formation.
The full paper reads like significantly weaker result than some of the other statements suggest. https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.061301
Skepticism is warranted. 12ka ghost footprints at Utah desert: https://as.cornell.edu/news/ice-age-human-footprints-discovered-utah-desert
Dating in Utah is both young enough to be after a founding population and has a dubious dating method: "Since there haven’t been any wetland conditions in at least 10,000 years or so that could have produced such footprint trails in this remote area of the Great Salt Lake desert, said Duke, the prints are likely more than 12,000 years old." Or, you could have had a monsoon rain for a few days that left atypical conditions in place.
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