A Does modified gravity somehow explain galaxies that don't need it?

AI Thread Summary
Proponents of modified gravity address the observation of galaxies that appear to function without dark matter by examining specific cases, such as NGC1277, which demonstrates characteristics of both rotational and pressure support. The ΛCDM model suggests these galaxies typically show a deficit of dark matter, while Modified Newtonian Dynamics (MOND) indicates that their acceleration exceeds the MOND threshold. Notably, galaxies like DF2 and DF4 are considered anomalies, but their interpretations are complicated by factors such as distance and potential misestimation of their proximity. The discussion highlights the importance of relying on scientific papers over popular articles for accurate information. Overall, the conversation emphasizes the ongoing debate about the necessity of dark matter in explaining galaxy behavior.
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How do proponents of modified gravity explain the fact of observation of galaxies, the behaviour of matter in which does not require an explanation in the form of dark matter or modified gravity?
 
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Which galaxies are you speaking of?
 
NGC1277 is a lenticular galaxy, in between being rotationally and pressure supported. ΛCDM says those galaxies in general have a deficit of DM, and MOND says the acceleration is above the MOND turn-on. So both models say the same thing.

DF2 and DF4 are special, but a) AFAIK no other examples have been found, b) the interpretatiom depends on their distance, and c) there is some evidence that they are closer than supposed.

As a PS, popular articles tend to be substantially worse sources than the actual paper.
 
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