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A comment on Astronomers discover a strange galaxy without dark matter. Parent comment

Re:Astronomers discover a strange galaxy without dark matter by sahil50 on Wednesday January 12, 2022 @06:55PM (#29914632)
I look back to where this started, and this started with Fritz Zwicky noticing that galaxies and galaxy clusters are moving faster than expected. This is the root observation.

From there, a good question is "How do we model it?". And sqrt(GM/R^2 * cH/(2pi)) works really well.

By the way, cH/(2pi) = c^2 / (2pi * 13.8 bly), which looks like centripetal acceleration.

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Re:Astronomers discover a strange galaxy without dark matter by SiempreViernes on Wednesday January 12, 2022 @07:44PM (#29915232)
Galaxy rotation curves are really not the root observation behind structure formation though, those are two very completely different things.

I'm also struggling to find what MOND has to say about all the astrophysics observed that LCDM people try to model to get their Tully-Fisher to work. If MOND is true, why would all these astrophysical feedback effects (such as supernovae) not matter for Tully-Fisher?

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Re:Astronomers discover a strange galaxy without dark matter by sahil50 on Wednesday January 12, 2022 @09:43PM (#29916160)
The root observation is that galaxies and galaxy clusters are moving faster than expected, and holding together more strongly than expected.
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