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These successful predictions are all generally variants on modeling galactic dynamics, though. The trouble is that galaxies and galaxy clusters are very messy places, so it's hard to make sure you've incorporated all the relevant physics.

By contrast something like baryon acoustic oscillations are very simple to model, so you can be quite confident that you've incorporated all the relevant processes. And in that regime LCDM performs beautifully and MOND completely fails. So it's reasonable to suspect that in more complicated environments the problem is that we're not modeling the systems correctly rather than that there's new physics going on.



There are other predictions MOND makes. For example, it predicts higher collision velocities than LCDM, for example, see:

https://ieeexplore.ieee.org/document/8193356

And, of course, it predicted that the early universe would have bigger and more structured galaxies (which is what the posted article is about).

Dark matter has a slew of problems of its own; it's not the case that LCDM is problem free, despite good success in some areas.


MOND doesn't cover the existence of CBM, distribution of galaxies, non-metallic abundance - things all covered by LCDM.

What MOND has going for it is that galactic rotation curves are readily consumed by popsci readers and the story of the "little guy" vs the scientific establishment is an easily available frame story popsci authors can sell clicks for.

The proportion of lay people who think MOND could be true greatly outnumbers the proportion of MOND researchers and doesn't reflect the veracity of the theory.


MOND is not a cosmological theory unlike LCDM, and it isn't relativistic. So we should not expect it to cover the range of things that LCDM tries to.

It's just a tweak to Newtonian gravity, which surprisingly matches observation very well, and has accurately predicted quite a few things in the regime it operates in, before they were observed.

The fact it works so well in the areas it does apply to is the reason that science hasn't given up on it yet (regardless of what pop science or lay people think).


Very interesting. Do you know an article that ELI25 this?


For a more non-technical overview, Sean Carroll had a nice episode on his podcast where he talked about the evidence for dark matter among other things: https://www.preposterousuniverse.com/podcast/2023/07/31/245-...

For something more technical, this article just came out as an overview of the evidence for dark matter: https://arxiv.org/abs/2411.05062




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