| No. MOND predicts a large external field effect in the milky way due to satellite galaxies (like the large magellanic clouds). This would manifest itself in as "a reduced DM halo", and an keplerian decline (see figure in TFA). LCDM typically has a difficult time with this because in order to have a flat curve, the dark matter must be distributed in a halo that is MUCH bigger than the galaxy, and that leaves no explanation for the decline. Not having run the numbers, at first glance it looks like these new data are STRONG support for MOND. MOND also generally predicts that denser fast rotating galaxies should appear to have ~no dark matter (in these cases centripetal acceleration is > a0 constant, so it's in the Newtonian regime) , which is highly consistent with observations of galaxies. Naively (I have not run simulations) thinking about it it seems puzzling that the denser galaxies would have no DM -- since DM is supposed to be the nucleus for galactic formation in the early universe. Conversely, the galaxies that are highly diffuse (UDGs) seem to have extra dark matter, which is very consistent with MOND (since being diffuse, gravitational acceleration a < a0). Again, this makes little sense with LCDM as you would expect a pocket of extra DM to attract mass and nucleate the formation of a very dense galaxy. > separate dark matter from visible matter with some low probability in a galaxy merger Generally these observations have been done with weak lensing, and unfortunately there is not really yet a good model that reconciles GR with MOND. Apparently the math is hard. It is entirely possible that when you combine the two the calculated spacetime curvature solves to what you would expect from the observed weak lensing effects. |
> .. at the outskirts of the disk of the Galaxy, this [rotation] curve begins to decrease rapidly, following the prediction known as the Keplerian decline