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James Webb Space Telescope finds evidence for alternate theory of gravity

(thedebrief.org)
355 points jchanimal | 7 comments | 16 Nov 24 18:33 UTC | HN request time: 1.244s | source | bottom
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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. scotty79 ◴[17 Nov 24 03:42 UTC] No.42161818[source]▶
> because it doesn't agree with quantum mechanics

I don't think it doesn't agree. It's just that we never managed to neither formulate quantum mechanics on 4 dimensional space time nor quantize gravitational force. So we simply have no idea what happens in small scale in significant gravitational fieldd.

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2. naasking ◴[17 Nov 24 14:27 UTC] No.42164344[source]▶
We absolutely know GR is wrong, at the very least because of its singularities.
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3. scotty79 ◴[17 Nov 24 15:30 UTC] No.42164675[source]▶
All we can tell from singularities is that GR might have a realm of applicability ... like every other theory ever. Not that its wrong.
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4. anon84873628 ◴[17 Nov 24 17:20 UTC] No.42165396{3}[source]▶
"Has a realm of applicability" is what people mean by "wrong" here. As in, the equations we have don't fully generalize and explain all regimes. The "right" model will cover all regimes and still reduce to match what we already have.
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5. scotty79 ◴[17 Nov 24 17:23 UTC] No.42165422{4}[source]▶
Then every physical (and nature) law is wrong. Only math is right. There's not a single law that covers full regime for at least one definition of "full".
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6. naasking ◴[18 Nov 24 14:30 UTC] No.42172556{5}[source]▶
Possibly, but we're converging on something correct as we cover more regimes in this inductive process called science. That's the best we can do.
7. throwawaymaths ◴[18 Nov 24 19:50 UTC] No.42176195[source]▶
> I don't think it doesn't agree. It's just that we never managed to neither formulate quantum mechanics on 4 dimensional space time nor quantize gravitational force. So we simply have no idea what happens in small scale in significant gravitational fieldd.

I don't think MOND dosen't agree with GR. It's just that we never managed to formulate MOND in a spacetime compatible with GR. So we simply have no idea what happens on the galactic scale in a significant gravitational field.