Ahh, the latest "there's no dark matter, it's all just MOND" claim. The press release sounds awfully convincing, as usual, but every damn time one digs into MONDian claims, one finds they're at best heavily overstated. I'm doing a lengthy write-up on MOND versus CDM from a philosophy of science perspective, but I'll probably skip this particular claim.

The latest Gaia data indicates that Newtonian-like gravity is completely sufficient, and that the MOND-like behaviour, which should take over in the low acceleration regime if the idea is correct, is absent. It’s absent, in fact, at the ~16-sigma level: a tremendous significance. The paper that’s been getting the recent publicity... draws the opposite conclusion: claiming to see a better agreement with MOND than with Newtonian gravity, and at just over 5-sigma significance.

It’s not that someone is definitively right and someone is definitively wrong; it’s that there are assumptions that go into choosing and analyzing the data, and simply by making different assumptions (and not quantifying the associated errors that come along with making them), you can wind up drawing vastly different conclusions. This problem will always plague an observational science like astronomy, and is almost certainly the culprit behind another wild, dubious assertion that was made in 2023: that black holes are the cause of the dark energy in our Universe.

#Science
#Galaxies
#DarkMatter
#MOND

https://bigthink.com/starts-with-a-bang/binary-stars-prove-modified-gravity/