MOND (Modified Newtonian Dynamics) is an alternative to dark matter that explains the dynamics of stellar objects. One of the predictions of MOND is the ulta compact dwarf galaxies will have no apparent dark matter and will behave as Newtonian dynamics predict. In contrast, traditional dark matter theory doesn't definitively predict any particular result for any class of galaxies. Once again, the MOND prediction has been proven correct.
One of the basic problems with dark matter theory is that it doesn't predict much, because any discrepency between Newtonian predictions and reality can always be explained by assuming that there is dark matter to account for the difference. And, there isn't a very solid theory explaining where dark matter should be distributed and involves primarily post-hoc fitting of the data to reach its conclusions. Simply put, it has far more degrees of freedom than necessary to explain the data (in addition to the difficult that it relies upon the discovery of types of particles never observed.) It also, for example, does not explain trends in galactic color that MOND explains, while providing otherwise identical predictions of matter distributions to that of dark matter models.
MOND isn't a perfect theory by any means. Research is ongoing. And, it is only one of several members of a class of theories with the same basic approach. But, it does make definitive predictions that can be tested, and has repeatedly had its pre-data predictions confirmed as observation allows us to confirm or contradict them, and has a strong track record of being proven correct, except in galactic clusters and similar structures where mass is not very point like (such as the apparent starless galaxy recently discovered).
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