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> No, he's correct that each galaxy does need tuning. Specifically, the amount of DM and it's specific distribution is tuned to match each observation, which is
by sega_sai 4y ago
> No, he's correct that each galaxy does need tuning. Specifically, the amount of DM and it's specific distribution is tuned to match each observation, which is what the OP said.
Not true. The LCDM predicts the DM distribution with a typical DM profiles, and then the amount of baryons is heavily dependent on star formation, etc. Therefore each galaxy of the same luminosity will have somewhat different dark matter halo. Those are not tuning parameters at all.
Regarding the linked article, it an article written by proponents of MOND and is not objective. That is fine, but at the moment I don't believe MOND is a serious alternative, and the majority of the astro community would agree. Just the fact that MOND still requires dark matter anyway to reproduce CMB is major problem for it. But if someone develops the version of MOND that has equal predictive power to LCDM, I'll be happy to accept it, but we are not there.
- naasking 4y ago> Those are not tuning parameters at all. Then explain how MOND is able to make predictions that don't need such considerations. This suggests either that dark matter is superfluous, or that dark matter has some underlying order that reproduces MOND in some limit, thus eliminating the tuning needed. This is the approach taken by some superfluid dark matter models, which at least is not ignoring the problem. > Regarding the linked article, it an article written by proponents of MOND and is not objective Right, because anti-MOND or dark matter reviews are totally objective? > Just the fact that MOND still requires dark matter anyway to reproduce CMB is major problem for it It's not at all a problem to say we need DM like sterile neutrinos, since DM alone is insufficient to adequately explain all observations anyway.