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Newton's law of gravity passes its biggest test

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Re: Newton's law of gravity passes its biggest test

#11

Post by DonaldFisk »

Lvl999Noob wrote: post #7

I thought newtonian gravity was already proven to be inaccurate with Einstein's Special Relativity (or General Relativity?) giving better results on cosmic scales (basically analogous to an approximation vs an exact formula)?

General Relativity. It explained the anomaly in the precession of Mercury's perihelion, and the bending of starlight by the Sun (double the value predicted by Newton's law).

The test here is for the inverse square law of gravity. The rival theory in this case isn't GR, but MOND: https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics

Re: Newton's law of gravity passes its biggest test

#12

Post by ReptileMan »

sebzim4500 wrote: post #6
ReptileMan wrote: post #3

Earlier quoted context omitted.

Once I joked that a lot of things in the universe make sense if you view it as a "simulation with optimizations like lazy loading".

Yeah until you get to quantum computing and then it seems as if the universe is doing enormously more work than you would think necessary.

But only if someone observes it. The act of observation forces reality into existence.

Re: Newton's law of gravity passes its biggest test

#13

Post by cwmma »

GuB-42 wrote: post #2

If you follow Sabine Hossenfelder's channel, she has a MONDOmeter. With MOND (modified Newtonian gravity) on one side and dark matter on the other side. As new papers come out the needle goes back and forth, and I guess that she will make a new video if she hasn't already, with the needle moving one step towards dark matter. I find it interesting how it doesn't seem to settle. Dark matter is still the favorite, but t…

my understanding is that there are a few MOND champions who are still holding on to the idea while everyone else has moved on.

Re: Newton's law of gravity passes its biggest test

#14

Post by elashri »

GuB-42 wrote: post #2

If you follow Sabine Hossenfelder's channel, she has a MONDOmeter. With MOND (modified Newtonian gravity) on one side and dark matter on the other side. As new papers come out the needle goes back and forth, and I guess that she will make a new video if she hasn't already, with the needle moving one step towards dark matter. I find it interesting how it doesn't seem to settle. Dark matter is still the favorite, but t…

MOND is dead is a true statement if we say MOND is dead as a general theory of gravity. It does not mean is does not have its success with explaining galactic rotation curves but failing at mostly everything else.

Re: Newton's law of gravity passes its biggest test

#15

Post by davrosthedalek »

cvoss wrote: post #8
sebzim4500 wrote: post #6

Earlier quoted context omitted.

Yeah until you get to quantum computing and then it seems as if the universe is doing enormously more work than you would think necessary.

This comment and GP are two of the most concise and punchy descriptions I've ever heard of some of the deepest aspects of modern physics. On the one hand we have principles of locality and finite propagation speed, which limit the computational work to a small neighborhood, and on the other hand we have principles of non-locality and superposition, which cause the computation to explode as it swallows up potentially…

It might just be a reflection of the architecture the universe simulation is running on...

Re: Newton's law of gravity passes its biggest test

#18

Post by cowl »

GuB-42 wrote: post #2

If you follow Sabine Hossenfelder's channel, she has a MONDOmeter. With MOND (modified Newtonian gravity) on one side and dark matter on the other side. As new papers come out the needle goes back and forth, and I guess that she will make a new video if she hasn't already, with the needle moving one step towards dark matter. I find it interesting how it doesn't seem to settle. Dark matter is still the favorite, but t…

It's funny how for MOND we cant accept that it has some unknowns yet but we are more than willing to accept the FULL UNKNOWN Dark Matter. it's easy. put "Dark" in front of something and you don't have to explain it at all, no matter that something else explains at least 60-70% instead of 0.

Re: Newton's law of gravity passes its biggest test

#19

Post by fooker »

GuB-42 wrote: post #2

If you follow Sabine Hossenfelder's channel, she has a MONDOmeter. With MOND (modified Newtonian gravity) on one side and dark matter on the other side. As new papers come out the needle goes back and forth, and I guess that she will make a new video if she hasn't already, with the needle moving one step towards dark matter. I find it interesting how it doesn't seem to settle. Dark matter is still the favorite, but t…

We are likely going to find out that both are unfixably faulty.

It'll take either the next Einstein or some groundbreaking experimental observation to get there in my opinion.

If it was possible to incrementally fix these theories, the army of postdocs working on these would have already done so in the last decade or so.

Re: Newton's law of gravity passes its biggest test

#20

Post by fooker »

sebzim4500 wrote: post #6
ReptileMan wrote: post #3

Earlier quoted context omitted.

Once I joked that a lot of things in the universe make sense if you view it as a "simulation with optimizations like lazy loading".

Yeah until you get to quantum computing and then it seems as if the universe is doing enormously more work than you would think necessary.

Not necessarily.

You'd be correct given hidden variables.

But we know pretty convincingly that quantum anything does not have hidden variables.

https://en.wikipedia.org/wiki/Bell%27s_theorem

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