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Newton's Laws proved or disproved?

#2
With negative mass, if you push something, it accelerates toward you," said co-author Michael Forbes, assistant professor of physics at WSU.


They could call it the Shibusa Effect......
 
#3
#6
Einstein p1ssed on Newtons Law of gravity some time ago. The rest still stands.
 

Momba Womba

On ROPS
On ROPs
#8
Didn't they observe FTL signalling a while back, to triumphant coverage in the press, only to back pedal rather quickly when other teams found out that the equipment used to measure it was not used properly?
You may be confusing two experiments there - I think I heard Krauss discussing both.

They thought that they had observed nutrinos moving ftl - turned out that the measuring equipment was giving dud readings.

Faster-than-light neutrino anomaly - Wikipedia


Quantum entanglement sees communication move instantly across any distance, however there's no way to send information using it.

In physics, the no-communication theorem is a no-go theorem from quantum information theory which states that, during measurement of an entangled quantum state, it is not possible for one observer, by making a measurement of a subsystem of the total state, to communicate information to another observer.
No-communication theorem - Wikipedia
No-communication theorem - Wikipedia




Two nil to Einstein.
 

Momba Womba

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On ROPs
#9
Einstein p1ssed on Newtons Law of gravity some time ago. The rest still stands.
Bit harsh that, don't you think? Newton wasn't exactly wrong - he was just a bit limited in what he was able of observe. And he admitted as much.

Hitherto I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses, for whatever is not deduced from the phenomena is to be called an hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy. In this philosophy particular propositions are inferred from the phenomena, and afterwards rendered general by induction. Thus it was that the impenetrability, the mobility, and the impulsive force of bodies, and the laws of motion and of gravitation, were discovered. And to us it is enough that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea.
—Isaac Newton
 
#10
Einstein p1ssed on Newtons Law of gravity some time ago. The rest still stands.
Not really. Newtonian mechanics are a perfectly good set of approximations that work fine at low speeds and middle-of-the-road masses. Try and use them to describe the behaviour of black holes or electrons and you'll have problems. Use them to describe the motion of cars, people and planets, and you'll be alright.

Edited to add: One place where Einstein does score is his reasoning. Newton, to my knowledge, never made any attempt to explain *why* Newtonian mechanics worked. He just formulated the maths that described it. Einstein's notions of spacetime and reference frames didn't just give a better answer, it gave some insight into why the answers are as they are.

Still couldn't explain mass though :D
 
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#11
Bit harsh that, don't you think? Newton wasn't exactly wrong - he was just a bit limited in what he was able of observe. And he admitted as much.

Hitherto I have not been able to discover the cause of those properties of gravity from phenomena, and I frame no hypotheses, for whatever is not deduced from the phenomena is to be called an hypothesis; and hypotheses, whether metaphysical or physical, whether of occult qualities or mechanical, have no place in experimental philosophy. In this philosophy particular propositions are inferred from the phenomena, and afterwards rendered general by induction. Thus it was that the impenetrability, the mobility, and the impulsive force of bodies, and the laws of motion and of gravitation, were discovered. And to us it is enough that gravity does really exist, and act according to the laws which we have explained, and abundantly serves to account for all the motions of the celestial bodies, and of our sea.
—Isaac Newton
Unfortunately, he was wrong in the very essential of the relationship between space and time. He postulated separate space and time, with time being universal. Einstein overthrew this notion by showing that space and time should be treated as a single entity, space-time, with elapsed time being dependent upon the observer's frame of reference (including any mass or energy). See Spacetime - Wikipedia.

One of the major bits of evidence pointing to Einstein's General Relativity being correct, rather than Newton's gravity model, was that fact that Newton's gravitational model did not account for the motion of the celestial body Mercury. It was precessing other than in accordance with Mr Newton but pretty well in line with young Albert's calculations. This was all measured using mid 19th to early 20th century technology. See Tests of general relativity - Wikipedia.

Now, you may quibble that Newton got it good enough at low densities and relative velocities, and that is one reason that we continue to use Newton's model for most mundane calculations. But if that were the only criterion, we might be better off deferring to the older epicyclic model in some cases, as we could probably "explain" Mercury's precession more accurately ... after all, it can explain this!


See Deferent and epicycle - Wikipedia
 

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