Personal Topic

[Moronium]

Well, unless I should happen to conclude that I am moving, that is.  For SR such a conclusion is utterly blasphemous, and will quickly get you excommunicated from the church of SR.

 

But why should that be?  If all inertial frames are "equally valid" why shouldn't I be able to choose my own frame as the one that is presumed to be "moving?"  Why can't I conclude that, as an inhabitant of earth, for example, I am moving around the sun?

 

Because then the other guy (the sun in this example) and I would actually agree that his clock is faster and that mine is slower.  SR requires an irresolvable dispute between observers.  Each must insist, to his dying day, that HE is the one at rest and that the other guy is moving.  Without that conflict, SR, as a theory, self-destructs. The relativity of simultaneity goes out the window and the speed of light is no longer invariant in every inertial frame.

 

But what some fool who subscribes to geocentrism "insists on," really has nothing to do with physics, per se, does it? Then again, SR aint physics, it's philosophy/psychology.

 

A theory positing absolute simultaneity would never consider what an "observer" on either the earth or the sun would "think."  It would deal with both the sun and the earth as material objects in motion, that's all.  The conclusions it reached would be the same even if there were no "observers" on either mass.  And in such a theory, one object would "really" be moving (faster) than the other.  It wouldn't be a matter of interpersonal disputes, with each person proclaiming that he, and only he, is "right."  SR absurdly declares that both are right, but ONLY if each claims he is at rest.

Edited February 8, 2019 by Moronium

[ralfcis]

As incredibly uninformed as these posts are (and there's no way to inform these people), my last post has convinced me that there is no practical need for relative velocity to explain relativistic phenomena. I no longer care how relativity explains things in a completely empty universe. I no longer care that Bob and Alice have to re-unite to officially determine permanent age difference or that age difference has to be agreed on by all perspectives. Every time measurement for the foreseeable future will be wrt the earth frame.

 

The muon example doesn't care that the earth's clock has dilated wrt the muon's clock, we only care that from our perspective the muon's clock has dilated. We don't care that the GPS clock needs to turnaround (orbit) wrt our clocks to validate permanent age difference when the results we're interested are in the reciprocal time dilation of the majority of the orbit. We don't care that the re-unification point of each orbit converts the satellite's time dilation into permanent age difference. We don't care that from the satellite's perspective our clocks dilate wrt its clock. We also don't care what a proton's perspective of the LHC's earth clock is. If Alice takes off for Proxima Centauri and she gets there in less of her time, she has aged less wrt earth time to get there and her reciprocal perspective that earth has aged less is meaningless. According to relativity, they must reunite to establish who has really aged less. If Alice turns around at .6c, she will prove she had indeed aged less. But if Bob takes off from earth to catch up with Alice once she crosses Proxima centauri, his speed relative to earth would need to be double .6c (.8824c) and in the end that double speed would prove Alice had aged less because he'd need to double his speed wrt earth to end up ageing less than Alice.

 

Can anyone provide me with an example where reciprocal time dilation and a preferred earth-centric frame fails to give the correct result for age difference? If not, what's the point of the spacetime path rules to establish permanent age difference? What's the point of bringing in "acceleration" to resolve the reciprocal time dilation paradox? I've lost my religion.

 

And Moronium, just because we now are saying the same things does not mean I agree with you on anything because how you arrived at your conclusions is based on a total lack of understanding.

Edited February 8, 2019 by ralfcis

[Moronium]

my last post has convinced me that there is no practical need for relative velocity to explain relativistic phenomena...I've lost my religion.

 

And Moronium, just because we now are saying the same things does not mean I agree with you on anything because how you arrived at your conclusions is based on a total lack of understanding.

 

Well, at least we agree in principle, eh, Ralf?   You're wising up fast, boy.

[exchemist]

From wiki, which always has something to say about virtually everything:

 

.

https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence#History

 

It's probably worth noting that Poincare (like Lorentz) never accepted SR as being physically valid.  They conceded that it was just as mathematically valid as their own theories, but they both adopted a framework which presupposed absolute simultaneity and absolute motion as being "physically" correct.

 

As previously noted, their theories, or some slight variation on them, have been confirmed just as often (actually more often than) as SR.

Yes but Poincare was not able to show that it universally applies. He only saw it as true for EM radiation, so far as I know. It was Einstein, surely, who generalised  it and linked it to the other phenomena that SR accounts for. 

[exchemist]

Once again, SR is NOT the L.T. (which Einstein took from Lorentz), although many people seem to think the two are identical.  In particular they think that if the LT have been confirmed, then, ipso facto, SR has been confirmed.

 

 

https://en.wikipedia.org/wiki/Lorentz_factor

I don't see much distinction. Lorentz and Fitzgerald had got the maths empirically, but it was, Einstein, was it not, who was able to derive the same maths from the principle of relativity?

[ralfcis]

Just for fun I'm going to go back on the physics stack exchange and share my latest findings and see how long I last before I get a permanent ban and my IP gets blocked. Or maybe some meaningful dialogue will come out of it.

[Moronium]

I don't see much distinction. Lorentz and Fitzgerald had got the maths empirically, but it was, Einstein, was it not, who was able to derive the same maths from the principle of relativity?

 

 

You don't see any distinction between the LT and SR?  Or between the LT and LR, for that matter?  I guess that's my point.  Too many people are unfamiliar with the hypothetical premises of each theory.  They both employ, as a tool, the LT, but neither of them are the "same thing as" the LT.

 

The maths can be derived from either theory.  What special difference do you think deriving it from the principle of relativity (assuming that's even the source, which it doesn't appear to be) makes?  I'm missing your point.

 

Between deriving them from empirical observations or from "principles" I, as did Einstein himself, would prefer the empirical basis.  Einstein himself said his "principle" approach was inferior, but that he didn't have anything better to offer.

Edited February 8, 2019 by Moronium

[Moronium]

Yes but Poincare was not able to show that it universally applies. He only saw it as true for EM radiation, so far as I know. It was Einstein, surely, who generalised  it and linked it to the other phenomena that SR accounts for. 

 

The original question here was whether the formula can ONLY be derived from SR.  The authorities I've cited say no.  Are you claiming otherwise?  If a formula can be derived in a variety of ways, from a variety of premises, what difference does it make who derived it first?  The Scientific American article I cited showed that, as early as 1901, Poincare saw that E=Mc2 was theoretically implied by certain (fictitious fluid) assumptions.  The exact mathematical formulation was there, even if he didn't claim to have proved it. 

 

Of course the same article says that Einstein did not prove it either.

 

For that matter, another article I cited said it was experimentally disproven around 1980.

Edited February 8, 2019 by Moronium

[exchemist]

You don't see any distinction between the LT and SR?  Or between the LT and LR, for that matter?  I guess that's my point.  Too many people are unfamiliar with the hypothetical premises of each theory.  They both employ, as a tool, the LT, but neither of them are the "same thing as" the LT.

 

The maths can be derived from either theory.  What special difference do you think deriving it from the principle of relativity (assuming that's even the source, which it doesn't appear to be) makes?  I'm missing your point.

 

Between deriving them from empirical observations or from "principles" I, as did Einstein himself, would prefer the empirical basis.  Einstein himself said his "principle" approach was inferior, but that he didn't have anything better to offer.

Well obviously a derivation from an underlying principle has deeper explanatory power than a mere observation. That's why we bother with theories in science. We build models to account for the observations and predict further ones. Just as Planck's original exercise in obtaining the curve for black body radiation was empirically right but lacked an underlying explanatory model until QM started to be developed. 

[exchemist]

The original question here was whether the formula can ONLY be derived from SR.  The authorities I've cited say no.  Are you claiming otherwise?  If a formula can be derived in a variety of ways, from a variety of premises, what difference does it make who derived it first?  The Scientific American article I cited showed that, as early as 1901, Poincare saw that E=Mc2 was theoretically implied by certain (fictitious fluid) assumptions.  The exact mathematical formulation was there, even if he didn't claim to have proved it. 

 

Of course the same article says that Einstein did not prove it either.

 

For that matter, another article I cited said it was experimentally disproven around 1980.

Yes. My understanding is that to justify the formula as being generally applicable needs SR. The other derivations would appear to be specific to EM radiation and lack rationale for extension to all form of energy.

[Moronium]

Well obviously a derivation from an underlying principle has deeper explanatory power than a mere observation.  

 

Are you familiar with Einstein's own discussion of the inferiority of a "principle" theory to a "constructive" theory?  Or that of any other expert?  I don't think you're grasping the significant difference here.

Edited February 8, 2019 by Moronium

[Moronium]

Yes. My understanding is that to justify the formula as being generally applicable needs SR. The other derivations would appear to be specific to EM radiation and lack rationale for extension to all form of energy.

 

 

How do you respond the the paper I cited which said Einstein did NOT derive it from SR to begin with, but rather from Maxwell's equations?

[Moronium]

Yes. My understanding is that to justify the formula as being generally applicable needs SR. The other derivations would appear to be specific to EM radiation and lack rationale for extension to all form of energy.

 

You can "derive" a principle from one source (say an apple falling from a tree) and then attempt to extend it (say all the way to the moon) and then extend it more (say to the entire solar system), as Newton did.

 

How widely you apply it is an entirely  different question than the source of it's derivation.

 

You have to derive it (say it's a formula, like E=Mc2) in the first place before you can "extend" it.

Edited February 8, 2019 by Moronium

[exchemist]

How do you respond the the paper I cited which said Einstein did NOT derive it from SR to begin with, but rather from Maxwell's equations?

Well that's natural. He started the same way as Poincare - or, in a different context, Planck. But he didn't stop there. He looked for an underlying rationale and found it.

 

His contribution to the photo-electric effect was similar. The effect was known, but he saw a common link with Planck's black body work - which got him his Nobel Prize of course.  

[Moronium]

Well obviously a derivation from an underlying principle has deeper explanatory power than a mere observation. 

 

No, that's wrong. That's the problem with a "principle" theory as opposed to a "constructive" theory. A "principle" theory explains NOTHING. It merely posits it and that's the end of it.

Edited February 8, 2019 by Moronium

[Moronium]

No, that's wrong. That's the problem with a "principle" theory as opposed to a "constructive" theory. A "principle" theory explains NOTHING. It merely posits it and that's the end of it.

 

 

Here's an "explanatory" principle for you:  God knows best, and always assures that the best will happen.

 

Kinda like Liebniz's "principle of sufficient reason," ya know?

 

Assuming that, then everything is "explained."  True, it may lead to seemingly contradictory claims, but that's tough.  Just accept them.  Unless you're willing to reject the principle. But do so at our own risk.  Hell, you may get burned at the stake for being a heretic.

Edited February 8, 2019 by Moronium

[exchemist]

No, that's wrong. That's the problem with a "principle" theory as opposed to a "constructive" theory. A "principle" theory explains NOTHING. It merely posits it and that's the end of it.

There is no such thing as a "principle theory" as opposed to some other sort.

 

All theories in science need to be tested against observations, to be taken as valid.  A theory that replaces a series of ad hoc fits to data with an underlying principle that unifies them is obviously a step forward.