Newbie vs Einstein: Questions about Time Travel and Quantum Entanglement

[RandallB]

RandallB, a body at rest, in my hypothetical, would not reach infinite acceleration from an external force. Rather, it would accelerate quickly for an instant, and then quickly be slowed due to the inertia it acquires through motion through the ether.

Re Einstein and the ether, I definitely recommend you read Kostro's book, ...

hypthetical nonsense - inertia does not "slow" things down it resists the change. your version of "zero" inertia would need to instantly turn on to its full value of 'mass' with any move, that you could never see that it might have been "zero".

I'm satisfied that this "new ether" is better understood as attepting to "Construct" a defined field model, from the detail in the Janssen paper you recommended.
I see where your going and I understand how you missreading the meaning.
Look over chapter four there again and think through the types of Theorys (Constructive vs Principle), much more important than the notion that Einstein was supporting an ether.

 

[Nickelodeon]

I'm finding it difficult to see how a 'new ether' could effect acceleration but have no effect on linear motion (obviously, otherwise satellites would quickly slow down). Sorry if it has already been explained in the thread but haven't read it all.

 

[JustinLevy]

RandallB, a body at rest, in my hypothetical, would not reach infinite acceleration from an external force. Rather, it would accelerate quickly for an instant, and then quickly be slowed due to the inertia it acquires through motion through the ether.

You've admitted yourself that Einstein, even when he referred to space as 'ether', it was still relativistic. So you clearly are not talking about GR, nor are you talking about whatever you think Eintein's 'ether' is (since you seem to think this is separate from GR).

These ideas you are presenting, are old discarded (due to experimental evidence to the contrary) ideas of empty space being a physical medium the aether. Stop blatantly promoting such ideas on this site. If you want to discuss your own personal theories, refer to the independent research guidelines for these forums.

IMO this is where Einstein Theory is unrealistic...

A Theory of Principle does not need to show constructive explanations or direct constructive evidence of a unrealistic “truth” of extra dimension(s) (invisible to us) to allow for “Space-Time” warping etc.

The curvature of spacetime in GR is an intrinsic curvature, not an extrinsic one. You don't need to embed our spacetime into some higher dimensional Euclidean space to show the curvature.

 

[RandallB]

The curvature of spacetime in GR is an intrinsic curvature, not an extrinsic one. You don't need to embed our spacetime into some higher dimensional Euclidean space to show the curvature.

Matches with what I said so I don't see your point.

The curvature is a part of the higher demensional space that we have no realistic model for in our eucliden experiance. Hence GR is not a Realistic Theroy built from a constructive approch. Unrealistic does not make it wrong (Ref:QM) it just required building from "Principels".
Confirming the Principels as correct was a matter of making predictions to be tested as they were. It is still a "unrealistic" or “Theory of Principle”. The remaining question for GR is the conflict with QM.

 

[JesseM]

The curvature is a part of the higher demensional space that we have no realistic model for in our eucliden experiance.

No, it's only your "euclidean experience" that makes you think there is a need for a "higher-dimensional space" for a curved GR surface to be embedded in. If you drop those Euclidean intuitions, there is absolutely nothing illogical or self-contradictory about the notion of a curved 4D surface that is not sitting in any higher-dimensional space.

Hence GR is not a Realistic Theroy built from a constructive approch.

Can you define "realistic" and "constructive"?

 

[JustinLevy]

Matches with what I said so I don't see your point.

The curvature is a part of the higher demensional space that we have no realistic model for in our eucliden experiance.

How can you say that, and then in the very next sentence again repeat the exact opposite of what I was trying to tell you?

Maybe my explanation wasn't clear. Do you know what extrinsic and intrinsic curvature is?

Hence GR is not a Realistic Theroy built from a constructive approch. Unrealistic does not make it wrong (Ref:QM)

You are worrying me here. GR is a classical theory, and doesn't require the 'shut up and calculate' type attitude of QM.

Historically there are people who for some reason thought there was no way to understand relativity and one had to just 'shut up and calculate'. One such example in Dingle. He taught relativity and even wrote a textbook on it. It is clear from his book that he had this type of approach to relativity. Later, since he never really learned the physics behind relativity apparrently, he disavowed it and had huge arguments in Nature and even a newspaper with scientists over relativity. He is heralded to this day by crackpots. Taking the view that one must just accept GR and calculate without questioning is a very very sad state.

As another example, did you know that there was a fully relativistic theory of gravity proposed before GR? It even reduced to Newtonian mechanics in the right limit. However it was not a metric theory (the metric was not a dynamic variable), and was later shown to be incompatible with experiment. GR has real physics behind it. It is not just an abstract extension.


As contrast, the reason QM basically requires a "shut up and calculate" attitude is that it essentially is incomplete (often referred to as "foundational issues"). We hope to one day have a better hold on these foundational issues (the "measurement problem" in particular), and people continue to offer ideas and experimental tests to constrain these ideas. This doesn't mean it is unfounded, or has no physical meaning (in contrast, people have built up quite good intuitions and physical understanding of quantum systems), it just means for the measurement problem, when ever coupling to a classical system is involved we need to just take the positivist view and "calculate". Mainstream physicists don't believe QM is wrong, but the foundational uneasiness is there for a reason. To claim there is similar uneasiness with GR is false. GR is a classical theory and doesn't have these issues.

 

[Tam Hunt]

I'll circle back to previous objections to my hypothetical in a later post, and address here the "constructive theory" vs. "principle theory" issue. Einstein's history on this issue is also interesting and complex. Einstein always focused on creating principle-based theories. Obviously, SR is one such theory, with its two key postulates (constancy of c for all observers and constancy of physical laws in all inertial frames). SR led to some strange consequences, such as the asserted malleability of space and time, which must follow from the asserted constancy of c for all observers (b/c speed is measured in m/s or whatever units you prefer, reflecting space and time).

GR is similar, of course. But Einstein disagreed, however, with the notion that his theories were "just mathematical games" and he argued, to the contrary, that reality really was as strange as his theories asserted. He struggled with positivism vs. realism, beginning his career as a Machian positivist (only things that can be measured should be part of physical theories) and changed mid-career to a realist, arguing, for example, that reason alone required there be a relativistic ether, even though it seemed to be undetectable even in principle. This is the key example of where he began to break from Mach. Again, from his 1920 Leiden speech:

To deny ether is ultimately to assume that empty space has no physical qualities whatever. The fundamental facts of mechanics do not harmonize with this view... Besides observable objects, another thing, which is not perceptible, must be looked upon as real, to enable acceleration or rotation to be looked upon as something real ... The conception of the ether has again acquired an intelligible content, although this content differs widely from that of the ether of the mechanical wave theory of light ... According to the general theory of relativity, space is endowed with physical qualities; in this sense, there exists an ether. Space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any spacetime intervals in the physical sense. But this ether may not be thought of as endowed with the qualities of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it.

And an interesting exchange related by Isaacson, in his biography of Einstein (p. 332):

“A new fashion has arisen in physics,” Einstein complained, which declares that certain things cannot be observed and therefore should not be ascribed reality.
“But the fashion you speak of,” Frank protested, “was invented by you in 1905!”
Replied Einstein: “A good joke should not be repeated too often.”

 

[Tam Hunt]

Justin, as my last post indicates, I agree with you that Einstein and the large majority of modern physicists and philosophers think that SR and GR actually describe reality. But your point about the ether being a debunked theory is just wrong. As I've mentioned already, the Higgs field is the newest version of the ether - a relativistic ether. And even if the Higgs boson is not found, it is still quite clear that space has its own properties independent of matter, as is revealed by QM and the seething morass in the vacuum that it predicts.

Check out Reg Cahill's work on the quantum foam 3-space, which is akin to the new ether. All things come from this 3-space, which is an information-theoretic network. Cahill is highly controversial, so be warned! He argues strongly for absolute motion due to his belief that numerous experiments (including his) have actually detected an anisotropic (non-constant) speed of light, contrary to the usual interpretation of Michelson/Morley and other similar interferometer experiments.

 

[ZapperZ]

This thread has deteriorated into mainly a discussion on history, rather than physics. It no longer belongs here. If people wish to continue such a discussion, please do so either in GD or in the Social Science forum.

This thread is done.