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Last I read, such galaxies aren't a problem for MOND. MOND doesn't say that all matter in the universe is detectable, it just says that due to modified gravity,
by tynpeddler 5y ago
Last I read, such galaxies aren't a problem for MOND. MOND doesn't say that all matter in the universe is detectable, it just says that due to modified gravity, the apparent missing mass we observe can be explained by dust or some other cold baryons.
MOND has explained similar galaxies in the past by postulating that there's very little dust.
- 8note 5y agoIf mond has dark matter anyways, why bother with mond?
- vardump 5y agoI think (s)he meant some kind of theory that's basically MOND, but with still some dark matter included. Dark matter and MOND might not exclude each other.
- throwawayffffas 5y agoBecause that could be the actual physical reality, gravity or inertia might not fully work how we think it does, and there might also be some stuff we can't detect. The objective should be to make correct predictions and understand how things actually work not for one side to win the argument.
- tynpeddler 5y agoThe term "Dark Matter" refers to an unknown kind of matter that interacts gravitationally but not electromagnetically. My comment is referring to cool baryonic matter, ie the same kind of matter than you and I are made of. In other words, MOND explains galaxy dynamics by modifying gravity and postulating the existence of small amounts of conventional matter that are below the detection threshold of our telescopes. Dark matter theories explain galaxy dynamics by postulating the existence of huge amounts of an exotic matter (alongside some conventional dust) that we can't see and haven't been able to detect in any experiments.