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James Webb Space Telescope finds evidence for alternate theory of gravity

(thedebrief.org)
357 points jchanimal | 2 comments | 16 Nov 24 18:33 UTC | HN request time: 0.919s | source
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uoaei ◴[16 Nov 24 19:50 UTC] No.42158729[source]▶
I follow the lead author, Stacy McGaugh, via his blog where he posts discussions and musings about the latest research into the dark matter vs MOND debate: https://tritonstation.com/new-blog-page/

His arguments are very convincing and relatively clear. I am not an astrophysicist but I have two degrees in physics and have always found the dark matter theory to be lacking -- in absence of any evidence of causation whatsoever, dark matter can only be described trivially as "where we would put matter if we could to make our theory of gravity make sense," which is totally backwards from a basic scientific perspective.

Predictions based on modern MOND postulates are shown to be more and more accurate as our observational instruments continue to improve in sensitivity.

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simonh ◴[16 Nov 24 20:07 UTC] No.42158855[source]▶
I don’t think that’s quite fair. That approach is exactly how we find planets. Here’s an unexpected variance in the motion of a planet or star. It could be explained by a planet over there. Oh look, there’s a planet over there.
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solid_fuel ◴[16 Nov 24 20:16 UTC] No.42158941[source]▶
Hypothesizing that a planet might be over there is a testable hypothesis.

Have we found a way to verify the presence of dark matter yet? Or is it still an untestable hypothesis sprinkled around distant galaxies so their acceleration curves look right?

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mr_mitm ◴[16 Nov 24 20:54 UTC] No.42159237[source]▶
Dark matter predicted lensing effect which were successfully tested. Same for the baryonic acoustic oscillations in the CMB.
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MattPalmer1086 ◴[16 Nov 24 21:15 UTC] No.42159414[source]▶
That's not quite true. General relativity predicts gravitational lensing, not dark matter. Lensing has been used as an experimental probe for the presence of dark matter.
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1. elashri ◴[16 Nov 24 21:21 UTC] No.42159464[source]▶
MOND is an alternative theory of gravity competing with GR. People usually forget that while MOND started to present a different explanation for Dark Matter, it is a theory of gravity. Dark Matter is not a theory of gravity and is compatible with GR.
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2. zeroonetwothree ◴[16 Nov 24 22:10 UTC] No.42159811[source]▶
Dark matter isn’t much of a theory in the first place.