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Comment by MattPalmer1086 | Hacker News Reader

Also see [1], a follow up post by Stacy McGaugh, a MOND proponent, who is quoted in the Quanta article. He does not agree with the evidence as presented in that article.

[1] https://tritonstation.com/2026/10/15/ghostly-galaxies-in-the...

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According to MOND theorists, a dwarf galaxy like DF9 doesn't prove dark matter, since it's sitting in the gravitational field of a big neighboring galaxy (NGC 1052) and thus its boost is suppressed. They call this the "external field effect".

https://arxiv.org/abs/2104.13961

“We don’t know what dark matter is or how to directly measure it but this distant galaxy has none”

Ok then

> DF2 has consistently been portrayed as fatal for MOND despite consistently being shown not to be a problem. I’ve given up writing formal papers showing this, as nobody cares. They just hear what they want to hear, which is that MOND is wrong. Indeed, after the 2018& incident I swore off doing so.

This should set off crank alarms when you read it.

Professor McGaugh has commented many times on the sociology of science and how the dominant paradigm tends to be hostile or indifferent to alternate views. He is also quite frank about the limitations of MOND as well, although he is definitely in the MOND camp overall.

He is hardly a crank - but he is definitely not in the mainstream camp.

perusing his blog posts, basically if a calculation is at all within expected values, this is evidence of MOND, but for something to be evidence of dark matter it has to jump through quite a few hoops in his opinion.

He also seems to have the same problem that many MOND proponents have which is arguing for MOND in blog posts instead of in papers, though he doesn't seem to be as bad as others in this regard.

He is a professional scientist with a blog - he has written a lot of papers as well [1]. It is worth taking his views seriously, even if you have reason to dispute them.

[1] https://scholar.google.com/citations?user=lM8J8noAAAAJ&hl=en

> Professor McGaugh has commented many times on the sociology of science and how the dominant paradigm tends to be hostile or indifferent to alternate views

This should also set off crank alarms.

Maybe it should - but it does not prove that the subject is a crank. Thomas Khun's theory of paradigms shows that science is not an entirely objective undertaking.

Having read Prof McGaugh's blog and some of his published papers for quite some time, I do not place him in the crank bucket. Make your own mind up I guess. My take is he is a legitimate scientist who holds views outside the mainstream.

I remember object-oriented programming being on the same pedestal when I was younger and first learning programming—a lot of OOP folks and mainstream programmers were definitely hostile to other schools of thought like functional or procedural programming.

Hell, I've worked with programmers who, entirely honestly, treated "object oriented programming" as a synecdoche for good programming...

The biggest problem with MOND is that it was hand-crafted with additional parameters simply to fit the data. What's missing is a reason or a mechanism by witch gravity stops following the inverse square. Scientists generally take a dim view of such theories.

"With four parameters I can fit an elephant, and with five I can make him wiggle his trunk." John von Neumann

MOND has one constant parameter, a0. This is hardly a good example of a theory tweaking many parameters to fit the data.

Yes, it is empirically determined and provides no deeper insight into why it works.

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