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but... this is not true? McGaugh himself [1] mentions that there are mass discrepancies even using MOND analysis, and that this favors the dark matter paradigm [2].

[1] https://twitter.com/dudedarkmatter/status/109452639162072268... [2] https://twitter.com/DudeDarkmatter/status/109452792999493222...

certainly, these are still open questions in cosmology

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The tweets above are good questions! This is how to do science!

Meanwhile it's good to restate the obvious.

Modified gravity (MOND), where acceleration at galactic scales isn't just GM/R^2 but modeled as sqrt(GM/R^2 * cH/(2pi)), works for 100s of galaxies, and is more precise than cold dark matter (CDM).

Modified gravity only has one free parameter. cH/(2pi) = c^2 / 87 bly.

Can the free parameter be described by something other than dark matter though? Or does it only put more constraints on what the dark matter is.

Indeed. More detail here. https://news.ycombinator.com/item?id=29915004

Perhaps the "dark matter" of a galaxy is the rest of the galaxies of the universe.

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