The article is not about MOND, it is about the falsification of Dark Matter. They do advocate MOND, but the main takeaway is right up front:
> The current cosmological model only works by postulating the existence of dark matter – a substance that has never been detected, but that is supposed to constitute approximately 25% of all the universe. But a simple test suggests that dark matter does not in fact exist. If it did, we would expect lighter galaxies orbiting heavier ones to be slowed down by dark matter particles, but we detect no such slow-down. A host of other observational tests support the conclusion: dark matter is not there.
The article tries to conclusively throw out good and predictive science based on a single rare edge case test that well-educated people believe to be explainable within the same paradigm.
If you're going to claim that dark matter doesn't exist, you need to have a way to explain all of the cases that are known to show that dark matter does exist. Cases like the Bullet Cluster, where a collision left all of the visisble matter in one region, and all of the gravitational matter in another. How can this possibly happen if there is no such thing as invisible gravitational matter? How can there be galaxies like AGC 114905 that don't have any dark matter, if there is no such thing as dark matter for galaxies to have or not?
DM falsehood does not depend on any other known thing being correct. It particularly does not depend on MOND being correct.
The honest fallback position is not "this other thing is better", it is, "We do not know. We had hoped we did, but were wrong." Then, start entertaining hypotheses that encompass all observations, without prejudice, not just favored ones.
So if DM is falsified and MOND is unworkable, what should scientists do? Just admit that they have no idea what's going on, but it looks a lot like missing mass?
>Just admit that they have no idea what's going on, but it looks a lot like missing mass?
The way I see things, the much more prevalent attitude is, "we have a good idea of what's going on, we just haven't been able to confirm our confident assessments with objective data". Very few, if any, prominent people in the field admit, "we don't have any idea what's going on, it is all baseless conjecture that might pan out if 75% of the universe is made of some invisible stuff that we haven't been able to detect in 4 decades despite our best efforts". I'd like to see a paradigm shift from, "we have a good understanding of how things work, now we just need to detect the invisible particles that make all of our formulas work" to "we have really have no idea what is happening, but here is some wild speculation that is the best we can come up with".
A lot of the "dark matter" debate reminds me of the Alzheimers/amyloid situation. Groupthink develops among the establishment in the field, based on very little (if any) objective proof, which ends up discouraging and marginalizing those who pursue other theories.
They are advocating MOND by omission. If you say dark matter isn't there you now need a theory that can explain all the observations that do support dark matter. MOND seems to be the only semi reasonable alternative.
It's perfectly reasonable to say, "your theory is full of holes and isn't based on anything objective that can be measured or proved" without coming up with an alternative theory. You can (and should in my opinion) point out things that are baseless conjecture whether or not you have a better idea. "I don't know" is something a lot of us would be better off saying more often.
I agree, it's fine to point out holes in a theory without an alternative explanation. However, it does still leave the problem of how else do you explain all the dark matter observations. So one must be careful not to give to much weight to those kinds of criticisms, as finding one hole in something that explains ten observations doesn't give much confidence in saying the whole theory is wrong (just an example.) Dark matter still seems a much better explanation than MOND to date, even if I personally feel it looks like a hack.
I don't think MOND proponents say the theory is complete, just that alternative gravitation theories is the direction that should be taken for research instead of funding futile dark matter detection projects.
> The current cosmological model only works by postulating the existence of dark matter – a substance that has never been detected, but that is supposed to constitute approximately 25% of all the universe. But a simple test suggests that dark matter does not in fact exist. If it did, we would expect lighter galaxies orbiting heavier ones to be slowed down by dark matter particles, but we detect no such slow-down. A host of other observational tests support the conclusion: dark matter is not there.