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James Webb Space Telescope finds evidence for alternate theory of gravity

(thedebrief.org)
355 points jchanimal | 4 comments | 16 Nov 24 18:33 UTC | HN request time: 0.001s | source
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samsartor ◴[16 Nov 24 20:21 UTC] No.42158987[source]▶
My hangup with MOND is still general relativity. We know for a fact that gravity is _not_ Newtonian, that the inverse square law does not hold. Any model of gravity based on an inverse law is simply wrong.

Another comment linked to https://tritonstation.com/new-blog-page/, which is an excellent read. It makes the case that GR has never been tested at low accelerations, that is might be wrong. But we know for a fact MOND is wrong at high accelerations. Unless your theory can cover both, I don't see how it can be pitched as an improvement to GR.

Edit: this sounds a bit hostile. to be clear, I think modified gravity is absolutely worth researching. but it isn't a silver bullet

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throwawaymaths ◴[16 Nov 24 23:35 UTC] No.42160543[source]▶
> My hangup with MOND is still general relativity.

Fwiw, we know for a fact also that for edge cases GR is wrong because it doesn't agree with quantum mechanics (unless QM is wrong), so it's maybe not right to take GR as gospel, especially for a theory that only seems to also change GR in edge cases, and the only reason why "it doesn't agree" might amount to "the math is hard and the physicists haven't put enough work in yet"

To wit, accepting a mond-ified GR is probably not going to change how GPS works so the claim that "GR has withstood the test of time and engineering" is not a totally solid refutation of MOND

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1. mort96 ◴[16 Nov 24 23:54 UTC] No.42160655[source]▶
Well this doesn't seem like such a conundrum. We know for sure that ND is wrong because it predict things incorrectly which GR predicts correctly. We know GR is wrong because it is incompatible with any form of QM and we know some form of QM is more or less correct. Essentially, GR and ND are both wrong, but ND is more wrong than GR.
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2. codethief ◴[17 Nov 24 15:34 UTC] No.42164694[source]▶
> we know some form of QM is more or less correct

This is a wild take, given all the issues QM and QFT have.

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3. RandomThoughts3 ◴[17 Nov 24 15:45 UTC] No.42164763[source]▶
> We know GR is wrong because it is incompatible with any form of QM and we know some form of QM is more or less correct.

It’s not really about one model being correct. GR is not a perfect model because its predictions don’t match what’s observed on the scale where QM gives predictions which do.

"Wrong" is overall a poor way of thinking about models. People would like a model which is both general and elegant, not simply a model which is "right". A large and very general model with a lot of parameters which can be well tuned to fit all the observations we have would be "correct" but I am not convinced it would be very useful.

4. mort96 ◴[17 Nov 24 17:03 UTC] No.42165281[source]▶
Sure, a better way of saying it is tat we observe natural phenomena which are explained by something like QM and for which we have no other explanation. I think people got the idea.