Entanglement spooky action at a distance

[peter0302]

I think you can figure this out as easily as anyone: IF Locality holds (the point of positing Superdeterminism in the first place) AND initial conditions control the ultimate outcome, THEN the outcome of every future experiment that is to be run must be present in every local area of the universe (so that the results correlate when brought together). The burden would be on the developer of this hypothesis to provide some explanation of how that might work. Thus, I will critique an actual superdeterministic theory once there is one.

I got it. Quantum DNA. The past and present history of every particle in the universe is encoded in every particle. There's your hidden variable.

This isn't as far-fetched as it sounds if each elementary particle is a single 4 dimensional line as Wheeler thought.

 

[RandallB]

I got it. Quantum DNA. The past and present history of every particle in the universe is encoded in every particle. There's your hidden variable.

This isn't as far-fetched as it sounds if each elementary particle is a single 4 dimensional line as Wheeler thought.

IMO it still does not address the issues in the last paragraph of both DR C post # 117 & my Post #118: i.e. still farfetched.
Since a Wheeler 4 dimensional line cannot be Local and Realistic, it would be a Non-Local hidden variable.

 

[peter0302]

Yes it's far-fetched but no more so than any other interpretation.

It's still local in the sense that there is no communication going on faster than light - there's no communication at all because every particle is one.

And it's actually hyper-realistic because there is a defined value for every particle throughout all of time and space.

Look I'm not saying I think this is true and am certainly not advocating it, I'm just saying that if you want a superdeterministic interpretation that is at least stateable, there it is.

 

[DrChinese]

I got it. Quantum DNA. The past and present history of every particle in the universe is encoded in every particle.

Now all we have to do is read it and we will know everything that is to come. :)

Obviously, everything else we know about elementary particles indicates they have no internal structure and do not have well-defined non-commuting properties outside of an observation. So "quantum DNA" is conceptually possible but little more. As I said, a specific theory would almost certainly be falsifiable. The concept only works as long as it is jelly - i.e. no specifics to critique.

 

[peter0302]

Of course you're right. The vaguer the better when it comes to interpretations. I guess that's why Copenhagen is so successful. :)

 

[vanesch]

I got it. Quantum DNA. The past and present history of every particle in the universe is encoded in every particle. There's your hidden variable.

Yes, that's what I call "god's book". "things happen".

 

[RandallB]

Yes it's far-fetched but no more so than any other interpretation.

It's still local in the sense that there is no communication going on faster than light - there's no communication at all because every particle is one.

And it's actually hyper-realistic because there is a defined value for every particle throughout all of time and space.

Look I'm not saying I think this is true and am certainly not advocating it, I'm just saying that if you want a superdeterministic interpretation that is at least stateable, there it is.

but it is Not “stateable” as a Local interpretation unless you ignoring what people mean when they say and hear “Local”.
They don’t mean local as in locality alone. They mean Local as in EPR Local requiring locality, and realism which includes causality.
And a hyper-realistic “DNA” does not qualify as EPR realism. IMO super-deterministic determinism cannot be presented as Local unless you redefine Local into something different than the EPR Local expected when that term is used.
To declare an interpretation requires a hyper-realistic version of realism defines it as Non-Local in any meaningful understanding related to EPR.

 

[peter0302]

Right I see what you're saying. There really is no such thing as causation in a quantum DNA theory or really any superdeterministic theory that I can imagine. The very idea of causation means that something different could have happened than what did, which would be impossible if everything's already been set in spacetime.

 

[ueit]

I think you are seeing the basic issues... entirely new mechanisms are required and once their assumptions are spelled out, it will be clear that the result is an ad hoc theory with a lot of baggage. Here is an example of the difficulty:

I. The Experiments

Experiment A: I simply hold Alice and Bob's observations at a 120 degree difference (i.e. static, no change from one reading to the next) and collect a sample of 10,000 readings. No choice is involved, at least from trial to trial. I expect the results to be a correlation rate of .25 as predicted by QM.

Experiment B: I set Alice and Bob's observations at a 120 degree difference (but dynamically, in which I personally "randomly" choose between whether the difference is to be +120 or -120 degrees by changing the orientation only of Bob's apparatus) and collect a sample of 10,000 readings. I expect the results to be a correlation rate of .25 as predicted by QM.

Experiment C: I force Alice and Bob's observations to be at a 120 degree difference by a dynamic mechanism (described in next paragraph) - choosing between whether the difference is +120 or -120 degrees by again changing the orientation only of Bob's apparatus -and collect a sample of 10,000 readings. I expect the results to be a correlation rate of .25 as predicted by QM.

This dynamic mechanism is as follows: I use a radioactive sample to generate random numbers. Say I use an algorithm based on the time of detection of the radioactive particle. If it ends in an even number then I set at +120 degrees, if an odd number I set at -230 degrees. This is done while Alice and Bob are in flight. Therefore, there is no possibility of an FTL influence.


II. Discussion of Issues

What are the issues here? All of the results are identical, as predicted by QM. But the Superdeterministic theory must now explain HOW that is possible because the conditions are being varied, in effect, by placing an experimental "barrier" between the initial time T=0 and the time of the actual test. Since A, B and C have different ways that the choice is made for the observation, we need the superdeterministic theory to explain how these 3 variations end up with identical results. This is also true for an infinite (or at least a large :) number of other variations (D,E,F...) that you or I can dream up.

So: how do the initial conditions NOT change the outcome when radioactivity (a random quantum process) is responsible for the selection of the measurement settings? Gee, there must be a causal connection between the radiation and the algorithm I am using to key off of as well. Then we now have a pretty big conspiracy going on between the different forces, quantum events and macroscopic objects as well, if we are to get the desired results.

The mistake in your line of reasoning is related to the scale you use to look at these experiments. The hypothetical local-deterministic law of motion is defining the dynamics at plank scale, not at the macroscopic scale.

We have good evidence that the electromagnetic, weak and color forces are but manifestations of the same fundamental interaction. We should therefore expect the same dynamics at Plank scale for every type of standard-model particle. This law of motion at Plank scale should therefore describe in a similar way uranium, silicon or carbon atoms and any combination of them like rocks, humans, computers and so on.

Seen from a macroscopic point of view each "different" experimental setup is the quantum analogous of different galaxies in general relativity. We shouldn't expect a different law of gravity for each type of galaxy or for each type of massive object (stars, neutron stars, planets, gas clouds, etc.). Why do you think we should expect a different behavior at Plank level when the microscopic attributes of the object change?

Since the distant results are to be correlated, the hypothetical causal connection is contained locally too. So all of this must be hiding somewhere in Alice and Bob; i.e. there must be information contained within these photons. And yet, the photons didn't even exist before they were created in the source laser.

The causal connection is "hiding" in the interactions between the particles contained in the source and detectors. The particle configuration in the detector (including whatever is supposed to change its orientation) produces a specific local field and this field determines the motion of the electron that later will emit the photons. Of course, a quantitative calculation of such a complex system will probably remain intractable for a very long time but this is also true for the standard QM.

III. Conclusion

So it should be clear that any proposed solution will suffer from an extreme case of ad hoc description which becomes very complicated very quickly. I don't think this is useful, and I don't think we are any longer talking about Bell's Theorem. And I don't think the theory we arrive at could withstand the objective assault that it would be subjected to. As I said to begin with, we could just as easily postulate that God personally tricks us into witnessing the results by biasing Bell tests... and this is just as reasonable (or unreasonable) as any Superdeterministic theory.

You should see by now the difference between a mathematically well defined, deterministic law of motion at Plank scale and a fuzzy concept like a god. In the first case there is no bias, the law is no different for human observers or something like that. EPR correlations should appear as an emergent consequence of that unique law of motion.

 

[DrChinese]

The mistake in your line of reasoning is related to the scale you use to look at these experiments...Seen from a macroscopic point of view each "different" experimental setup is the quantum analogous of different galaxies in general relativity. We shouldn't expect a different law of gravity for each type of galaxy or for each type of massive object (stars, neutron stars, planets, gas clouds, etc.). Why do you think we should expect a different behavior at Plank level when the microscopic attributes of the object change?...The causal connection is "hiding" in the interactions between the particles contained in the source and detectors. The particle configuration in the detector (including whatever is supposed to change its orientation) produces a specific local field and this field determines the motion of the electron that later will emit the photons...

...Hand-waving which ignores the point. It is up to the super-deterministic theory - of which none is being offered by you or anyone else - to explain that these setups lead to the same QM predicted results as we actually see. That the mechanics is at the quantum level was acknowledged, and certainly I am not arguing that there is not a connection between different forces. However, current QFT does not support any kind of interaction such as what you speculate might exist. You cannot simply throw out ALL other theory without providing a replacement.

There are strict requirements for serious theory development, just ask anyone who is working on string theory. You have the tail wagging the dog: in trying to save local realism, you are throwing out everything else we know. It works the other way: you need a mechanism that preserves what we already know, but adds something new and useful.

 

[Count Iblis]

't Hooft did first start with some attempts to develop deterministic theories. He only started to mention "superdeterminism" later to defend these attemps against the criticism that these attempts are a priori doomed to fail because of Bell's theorem.

 

[DrChinese]

't Hooft did first start with some attempts to develop deterministic theories. He only started to mention "superdeterminism" later to defend these attemps against the criticism that these attempts are a priori doomed to fail because of Bell's theorem.

Yes, and I think these attempts ARE doomed a prioi because of Bell's Theorem. I realize that convoluted escape mechanisms are appealing to those who see local realism as something that SHOULD be fundamental. But here is the ultimate challenge for any true local realistic theory:

IF i) a particle has well-defined non-commuting observables, AND ii) they have these values independent of the act of observation, AND iii) these values have an element of reality as defined by EPR, THEN you should be able to come up with some sample table of the values that matches Malus' Law (i.e. the cos^2 relationship predicted by QM).

But that is not possible. You can't construct ANY sample set of values for a photon's polarization at settings of A=0, B=120 and C=240 degrees which yields close agreement with the relationship that:

Correlation(AB)=Correlation(BC)=Correlation(AC)=.25 (QM predicted value)

I mean, if you can't even do that by hand-picking the values, how are you going to convince anyone that there are such real values?

So why isn't super-determinism (quantum DNA) a valid escape mechanism? Because Bell's Theorem only gave us one escape mechanism other than the rejection of realism. That is rejection of locality. 't Hooft should show us a specific point in Bell's Theorem which opens things up for his ideas. I think he has failed on this score to date. (Of course, no harm in trying - that's what these discussions are all about.)

Now we know that non-locality is a valid "escape mechanism" because perhaps an observation at Alice affects the outcome at distant Bob. But that in turn requires that we have a hypothetical non-local mechanism to accomplish same. Bohmian Mechanics has been offered as such a solution, although there is no other physical evidence of non-local forces.

But I would honestly question to what extent BM answers the question of the "realism" of the underlying non-commuting properties when they can never - in principle - be revealed. At least, not using the idea that EPR envisioned (i.e. entanglement).

 

[LaserMind]

If we have two entangled particles sharing three states (say spin, position, momemtum), then those three could collapse in any combination with respect to each other.

 

[ueit]

...Hand-waving which ignores the point.

On the contrary, I think I've honestly answer to each objection you have raised. Remember, we are speaking here about classes of theories that might be possible, not about developed theories. This is the point of finding no-go theorems, to see what is possible in principle.

It is up to the super-deterministic theory - of which none is being offered by you or anyone else - to explain that these setups lead to the same QM predicted results as we actually see.

I agree that this should be the goal of everybody that works on such a theory.

That the mechanics is at the quantum level was acknowledged, and certainly I am not arguing that there is not a connection between different forces.

OK

However, current QFT does not support any kind of interaction such as what you speculate might exist.

I don't think that a full QFT computation of such a complex system is possible. Last time I've checked the most complex system that has been solved was a two-particle system (pion). A three particle one (neutron, proton) was already too hard. So, nobody knows what exactly a quantitative QFT treatment of an EPR experiment would reveal.

You cannot simply throw out ALL other theory without providing a replacement.

I didn't imply such a thing. On the contrary, I specified that any interpretation should give you back the schrodinger equation. The purpose is to find an explanation that makes sense for a statistical correct theory (QM), not to reject the later.

There are strict requirements for serious theory development, just ask anyone who is working on string theory. You have the tail wagging the dog: in trying to save local realism, you are throwing out everything else we know. It works the other way: you need a mechanism that preserves what we already know, but adds something new and useful.

Yes, this is my position, too. The question is what type of mechanism one should search for. I think that a superdeterministic one is a viable option.

 

[vanesch]

I don't think that a full QFT computation of such a complex system is possible. Last time I've checked the most complex system that has been solved was a two-particle system (pion). A three particle one (neutron, proton) was already too hard. So, nobody knows what exactly a quantitative QFT treatment of an EPR experiment would reveal.

What you seem to miss is that in no matter what quantum theory (or for that matter, bohmian mechanics or whatever), we *specify externally* what are the measurements we are going to do. The theory can give an answer no matter what external input we use as "measurement settings". You don't have to follow through any complicated calculation to *find out* what measurement one is going to do, you put it IN by hand - in fact, there is not even any sensible way in which one could calculate, from first principles, what measurement one would do! EVEN if you could follow up through all the calculations - which is impossible in quantum theory, as well as in classical theory, and probably in ANY theory, current or future - you would still have to specify EXTERNALLY what's the measurement that is going to be performed (the choices of the angles, or the system that will determine this choice, or whatever) - it would be part of the description of the setup which you can (have to) arbitrarily determine before you could even start your (hopeless) calculation.

In other words, a quantum mechanical "problem description" contains not only the "correct" (superdeterministically correct) measurement settings, but all other, counterfactual, superdeterministically impossible, settings, and nevertheless grinds out an answer.

It is because of this freedom (external freedom, that is, we can do the calculations for all non-superdeterministically possible settings, and not only for the few superdeterministically allowed settings) that it is not going to be possible to demonstrate any *equivalence* between a superdeterministic theory and a non-superdeterministic theory such as quantum theory in all its variants, such as BM, MWI, or whatever.

You see, it is as if in classical mechanics, you would come up with a "super-configurational" theory that states that the positions of the particles also determine their momentum in some hidden way, and that this explains entirely classical mechanics. Now, you are not going to be able to show any equivalence with classical mechanics, because in classical mechanics, you are FREE to pick any momentum you like with a given particle configuration. You can do the classical calculation for all the "impossible" momentum assignments too out of which the "super-configurational" theory only picks one or a few possible ones. You are never going to be able to show that picking these few are going to be equivalent to the workings of classical mechanics, as most of the classical mechanics "initial conditions" are impossible in the new theory.
The only way to show this, is to demonstrate that if you do the entire calculation for those few specific allowed initial conditions, you nevertheless end up each time with all possible observable results from classical mechanics, with well-chosen initial conditions.

 

[ueit]

?? If there is a long-range force that's going to do the thing, then it is not local, right ? The quantum force in BM is not local, Newtonian gravity is not local, electrostatics is not local. What is local is a local field propagation equation, like Maxwell's equations or Einstein's equations. If you allow for long-range forces, then you don't NEED superdeterminism, as Bell isn't supposed to hold in that case. No, the only thing that is allowed are local interactions. That's what makes superdeterminism so hard to handle: the correlations must arise through a whole chain of local interactions from a certain "common initial state" up to the actual manifestation of the correlations, through the precise tuning of the "choices" of measurement in agreement with the particular sets of particles that have been emitted.

Sure, I have used the term "force" instead of field. I agree with what you say.

Yes, but also with the measurement process!

Sure.

In fact, that wouldn't be ok. In order for superdeterminism to hold, it must also do it in *the most complicated EPR test possible*.

Some theories cannot be scaled up easily. Quantum chromodynamics is such an example. GR might be another example. This doesn't mean they are wrong.

That would be a start, but then you'd have to show that those molecules appear in exactly those orientations, each time, to measure the photons along the right axis, each time. And then you must show that WHATEVER I ADD, that this is not going to change this. *this* is, IMO, the impossible task of showing superdeterminism.

You have the "source" atom evolving in the field generated by the "detectors" and anything else you might add. When this field has a certain magnitude and a certain orientation the entangled photons are produced as a function of this particular magnitude and orientation. I don't see the reason why the required correlation could not appear in this way. Now, you may be right and this could be impossible but this should be mathematically proven (as a new no-go theorem for example).

Because it would be sufficient to find one single system that doesn't orient the "detecting molecules" in exactly the anticipated way, to undo the entire system. Now, I know your objection to that: something like "conservation of energy" is superficially in the same situation, and we don't have to follow up on all possible engines to show the first law of thermodynamics. But there's a difference. In things like conservation of energy, there is a clear physical parameter which is conserved by each interaction, and hence, also overall. I don't see how one could introduce something like "conservation of choice" that makes that *this* photon, no matter how, is going to be analysed only with *that* analyser angle. If ever such a thing existed, it would mean we would have a relatively simple "thermodynamics of (non)free will" in all generality.

Again I don't think this question can be settled without a rigorous mathematical treatment. I agree that it doesn't sound very intuitive but this is also true for every other possible explanation of EPR.

No, there's a big difference. In QM, or classical physics, we *don't have to* follow up through all the nitty gritty detail, because it doesn't involve the *essential effect*. If a photon is detected with a PM, well, that PM is going to generate a signal and all that, and this is going to be recorded etc... but we don't need the details here because they don't matter. They don't compose the essential effect we are observing (detecting a photon). So this can be abstracted away without any difficulty.

However, if the process that makes Joe choose angle th1 is the essential mechanism, this is different.

Detecting a photon is not the same thing as checking the QM formalism against a complex system. I could claim, for example that QM does not apply to a human brain and you couldn't prove me wrong. I wouldn't make such a claim because I find the extant experimentally verification of QM satisfactory. And those verifications are limited to very simple systems like small atoms or (with some approximations) molecular bonds or solids that show periodicity (crystals).

 

[vanesch]

You have the "source" atom evolving in the field generated by the "detectors" and anything else you might add. When this field has a certain magnitude and a certain orientation the entangled photons are produced as a function of this particular magnitude and orientation. I don't see the reason why the required correlation could not appear in this way. Now, you may be right and this could be impossible but this should be mathematically proven (as a new no-go theorem for example).

You won't find a no-go theorem because it is very well possible. What I'm claiming is that I don't see how one could ever *demonstrate* a superdeterministic theory to be superdeterministic, even if it were. I'm claiming that the only way to PROVE that a theory is superdeterministic is to follow through the complicated relationship between "thing that apparently makes the choice of the measurement" and the emitted pair of photons.
Because *anything* could be used to set up the measurement angles (and that "everything" might be outside of the lightcone of the emitting atom at the event of emission, so your "in the field of the detectors" won't hold: take as an example remote starlight from opposite directions which decides the detector angles: when the emitting atom is emitting the pair of photons, this starlight is still on its way and couldn't have reached (or anything else at c couldn't have reached yet) the emitting atom). Even if a theory were superdeterministic, you wouldn't be able to demonstrate it, as it would involve a complicated follow-up which is FAPP impossible.

Again I don't think this question can be settled without a rigorous mathematical treatment. I agree that it doesn't sound very intuitive but this is also true for every other possible explanation of EPR.

Well, my point is that it won't be doable to demonstrate it. Even if we have it (without knowing).

Detecting a photon is not the same thing as checking the QM formalism against a complex system. I could claim, for example that QM does not apply to a human brain and you couldn't prove me wrong. I wouldn't make such a claim because I find the extant experimentally verification of QM satisfactory. And those verifications are limited to very simple systems like small atoms or (with some approximations) molecular bonds or solids that show periodicity (crystals).

I know that I cannot prove the claim that QM does or doesn't apply to the human brain. But the point is, *it doesn't matter* for the results. You can put the Heisenberg cut just anywhere, and it will yield in the majority of cases, the right result. So QM results do not NEED a detailed follow-up through a complicated chain of events, once you've the essential part - and that's in part because we can accept externally given "free will" decisions. But a superdeterministic theory CANNOT do that: it wouldn't give self-consistent results if we "forced" it into free will decisions which are not compatible with its dynamics which is supposed to generate superdeterministic correlations. So in a superdeterministic theory we have no choice but to follow up through all the complicated chain of events up to the "determined experiment choice".

 

[talmans]

I'm a layman and haven't studied entanglement or read deeply about the subject so I apologize if this is a tired question. Couldn't entangled particles be evidence of other dimensions? There is no spooky action at a distance because the particles aren't entirely separated.

Do any other theories allow for this interpretation?

 

[LaserMind]

I'm a layman and haven't studied entanglement or read deeply about the subject so I apologize if this is a tired question. Couldn't entangled particles be evidence of other dimensions? There is no spooky action at a distance because the particles aren't entirely separated.

Do any other theories allow for this interpretation?

I tend to 'think' along those lines to get answers for myself, although I have not seen an extra dimension to account for entanglement. A new dimension could be a little mathematical device we use to get answers with maybe some physical truth behind. Indeed, in QM two particles have 6 dimensions in the complex vector space already. So that's a start, but not quite what you mean.

It 'appears' that entangled particles behave, in certain ways, as if they are still very close to each other. As if distance and time do not apply to them. I rationalize myself with another dimension at work, rather than MWI, Superdeterminism, and am always reading any plausible offering with interest.

 

[Dragonfall]

What can we say about entangled pairs and their gravitational attraction? I know there's no quantum gravity yet, but take a guess.

 

[sudhirking]

what do u mean there is no quantumn gravity yet,,,,,,,
if you think about it, gravity itself is not by the mass of an objest other tham the curvature of quarks. so techinacally speaking, the only curvature there is iin quarks.

 

[jtbell]

what do u mean there is no quantumn gravity yet

There is no generally accepted theory of quantum gravity yet. It's a major area of theoretical research.

 

[sudhirking]

Becuase of what i said above, i believe that these quarks is undefined by our univesr because the smallest thing in this universe does not exist in our universe as the smallest thing would have a negative mass in awhich it could not be held by our universe but be in the antiuniverse. And since gravity only applies with quarks, our universe is the gravity of th e anti-universe. as for the entanglements, they could be fluctuations in the boundries between anti-universe and the regular universe

 

[sudhirking]

well that idea above uses my theory of everything ( WHICH I REALLY AM STILL EDITING BUT I WANT TO PUBLISH)
however i am self taught and i am only a freshman so i probably don't understand a lot of science. BUT I am so postitve my theory of everything is right, as it is everything it is supposed to be and fits wiht all current ideas and even applies quantum mechanincs to realativty and explains the inflamation theory.

But for one thing.: I AM SURE THAT GRAVITY ONLY WORKS WITH THE QUARKS AND THEREFORE GRAVITY IS ALWAYS QUANTUM!

PS what is a PF Mentor

 

[peter0302]

But for one thing.: I AM SURE THAT GRAVITY ONLY WORKS WITH THE QUARKS AND THEREFORE GRAVITY IS ALWAYS QUANTUM!

Why do electrons fall to the ground then?

 

[sudhirking]

Lol
because there are things smaller than elctrns
and they fall to the ground because the build of up of the ground contains more gracvity on a scale than comparred to he single electron.

 

[RandallB]

… that uses my theory of everything
however i am self taught and i am only a freshman

PS what is a PF Mentor

Ready to publish - Impressive.
Just curious is that a Freshman in HS or Collage?
Whatever level, you must agree that logically a reasoned discussion cannot happen if you’re the only one that knows anything about the unpublished ideas you wish to reference.

As to the PF Mentors, the very top “sticky” thread in the forum directed you to the Guidelines you need to read Before Posting. If you finishing reading those you see the Mentors mentioned about a dozen times.
Also, if you may not know what a PM is. Top right of the screen just below your name and time of last login. Is a count and link to any Unread Private Messages.
That will be where the Mentors can contact you if you don’t follow the guidelines.

Welcome to the forums, follow the guidelines and respect others opinions and you can learn a lot here. I you do publish something like on a website let me know in a PM, rather than in a post (read the guidelines).
RB

PS:
Normally advertisements are not acceptable in these posts, but IMO I think one is worthwhile here: Once you do see that you will learn a lot here – becoming a PF Contributor to give a bit of finical support is a worthwhile thing to do.

 

[DrChinese]

Lol
because there are things smaller than elctrns

Extensive experiments indicate that electrons act as point particles (i.e. they have no size) and certainly are NOT larger than quarks. Quarks also appear to be point particles but they are harder to analyze due to the effects of the strong nuclear force - so it is possible they have a very small size. Theory says they don't, and experiments have confirmed this within the limits mentioned.

Without extensive knowledge of the experiments that have been performed by scientists to date, you will have a difficult (actually impossible) time coming up with a "theory of everything". In fact, you will have a hard time coming up with a "theory of anything". Because any new theory must pass numerous very difficult hurdles in order to be accepted. These include an ability to explain already run tests, and the ability to make better predictions than existing theory in one or more areas.

There are forum guidelines, as RandallB pointed out, regarding posts regarding personal theories. These guidelines apply to everyone here, and there are plenty of recognized physicists in this crowd (I am not one of them though). The "rightness" of your theory won't matter if you haven't bothered to learn the basic science first. I commend your interest in original research and hope you can add to our knowledge some day.

 

[peter0302]

Lol
because there are things smaller than elctrns
and they fall to the ground because the build of up of the ground contains more gracvity on a scale than comparred to he single electron.

You have no idea what you're talking about, I'm sorry.

 

[Dragonfall]

What can we say about entangled pairs and their gravitational attraction? I know there's no quantum gravity yet, but take a guess.

Will no one hazard a guess?

 

[peter0302]

Their gravitaitonal attraction to what - each other? Undetectable. To the Earth? Sure - they theoretically fall to the Earth at 9.8 m/s2 like everything else. Of course we're usually talking about light which moves too fast in a lab to notice any gravitational influences. What is the question?

 

[RandallB]

Will no one hazard a guess?

Nothing
Not a Guess. I’m absolutely positive – IMO.

 

[Dragonfall]

What is the question?

The question is: how do you describe gravity of a system consisting of two entangled particles? How does it differ from the description of a system consisting of two non-entangled particles?

 

[wawenspop]

The question is: how do you describe gravity of a system consisting of two entangled particles? How does it differ from the description of a system consisting of two non-entangled particles?

I suggest that the field behaviours of the particles must obey relativity transformations in G and E fields, whereas the correlation of states is unaware of relativistic considerations because it is relieved of the responsibility of keeping the laws of physics the same in any (euclidean) reference frame and the combined entangled wave function needs, and has no relativistic correction - its FTL anyway.

 

[peter0302]

The question is: how do you describe gravity of a system consisting of two entangled particles? How does it differ from the description of a system consisting of two non-entangled particles?

I don't think you understand entanglement. Entanglement means that some property of the particle is defined by reference to the other. When that property is unamibuously measured in one, its value for the other is known.

The "gravity of a system consisting of two entangled particles" should be no different than in non-entangled particles.

Now I'll hazard a guess as to what you're getting at. If we have a neutron that decays into a proton and an electron, for example, the proton and electron are going to be entangled in their momentum, and they obviously are going to have different masses and charges, but they're technically not entangled in their mass and charge. The reason for this is that mass and charge are commuting observables. We can know mass and charge without changing them, so the HUP does not apply. When we talk about entanglement variables - position, momentum, spin, etc. - these are non-commuting observeables - which means that the order in which you observe them affects the results.

Gravity being solely a function of mass, there would be no special gravitational results observed in entangled particles versus non-entangled particles.

 

[ueit]

Sorry for the big delay, I was in vacation with almost no internet connection available.

You won't find a no-go theorem because it is very well possible. What I'm claiming is that I don't see how one could ever *demonstrate* a superdeterministic theory to be superdeterministic, even if it were. I'm claiming that the only way to PROVE that a theory is superdeterministic is to follow through the complicated relationship between "thing that apparently makes the choice of the measurement" and the emitted pair of photons.

I disagree. The superdeterministic character of the theory is only a consequence of the fact that the theory contains a (local) field that does not decreases quickly with distance (as the classical EM field does). The mechanism proposed by the theory can be verified statistically in different ways, not necessarily using EPR experiments. For example one can replace the resultant, pseudorandom field produced by all particles in the universe with a random field that has the same statistical properties (like the probability of the field to have a certain amplitude in a certain time interval). Then, one could model the dynamics of an atom or molecule in this random field and calculate the emission spectra. Because both the properties of the random field and the motion of the particles composing the atom/molecule are calculated using the proposed mechanism, a correctly predicted spectra is a proof of the theory. It is true that the theory predicts correlations between the emitted photons and the absorbers, and these cannot be verified so easily, but this is not a problem of the theory but of the experimentalist.

Because *anything* could be used to set up the measurement angles (and that "everything" might be outside of the lightcone of the emitting atom at the event of emission, so your "in the field of the detectors" won't hold: take as an example remote starlight from opposite directions which decides the detector angles: when the emitting atom is emitting the pair of photons, this starlight is still on its way and couldn't have reached (or anything else at c couldn't have reached yet) the emitting atom). Even if a theory were superdeterministic, you wouldn't be able to demonstrate it, as it would involve a complicated follow-up which is FAPP impossible.

It is not a theory's fault that you are not able to exactly describe your experimental setup. Using a computer simulation with a small number of particles (adding if you want some atoms that do not absorb photons but only randomize the "detectors" by colliding with them) is IMHO the way to go.

Well, my point is that it won't be doable to demonstrate it. Even if we have it (without knowing).

We could demonstrate it as I pointed above.

I know that I cannot prove the claim that QM does or doesn't apply to the human brain. But the point is, *it doesn't matter* for the results.

But it does. The experimental result is say the choice of tea over coffee. It is easy to perform the experiment. Now I want you to calculate the QM prediction for the experimental result.

You can put the Heisenberg cut just anywhere, and it will yield in the majority of cases, the right result.

IF you can calculate the result.

So QM results do not NEED a detailed follow-up through a complicated chain of events, once you've the essential part - and that's in part because we can accept externally given "free will" decisions. But a superdeterministic theory CANNOT do that: it wouldn't give self-consistent results if we "forced" it into free will decisions which are not compatible with its dynamics which is supposed to generate superdeterministic correlations. So in a superdeterministic theory we have no choice but to follow up through all the complicated chain of events up to the "determined experiment choice".

There is a similar problem in standard QM when you have complicated systems (like a brain). In the case of an EPR experiment the system of QM is 2 particles, while in the suprdeterministic (SD) theory is 2 particles + detectors + source. True, for this experiment, SD is not suitable to do the calculations. So what? You still can verify the theory by using smaller systems.

 

[vanesch]

I disagree. The superdeterministic character of the theory is only a consequence of the fact that the theory contains a (local) field that does not decreases quickly with distance (as the classical EM field does). The mechanism proposed by the theory can be verified statistically in different ways, not necessarily using EPR experiments. For example one can replace the resultant, pseudorandom field produced by all particles in the universe with a random field that has the same statistical properties (like the probability of the field to have a certain amplitude in a certain time interval). Then, one could model the dynamics of an atom or molecule in this random field and calculate the emission spectra. Because both the properties of the random field and the motion of the particles composing the atom/molecule are calculated using the proposed mechanism, a correctly predicted spectra is a proof of the theory.

You seem to forget that the particularity of a superdeterministic theory is that the essential correlations found, are due to specific correlations in the CHOICES made by the experimenters because their choices are not "free", and that if we allowed them to be truly random and independent, then the theory would NOT yield the correct results (THAT's what it means to be superdeterministic).

Let us take a toy example. Let us imagine that I have a switch and a light bulb. When I simply OBSERVE the switch states and the light bulb states, I see a perfect correlation: when the switch is "ON", the light is "ON", and when the switch is "OFF", the light is "OFF". This is an observed correlation, but it doesn't teach me much about any mechanism behind it: are the switch and the light bulb both activated by a common mechanism ? Is the switch causing the light bulb to go on and off ? Is the light bulb causing the switch to go on or off ? Is this just a weird correlation in nature ? Difficult to say.

However, in "normal" deterministic theories, we take it that we can CHOOSE the state of the switch. I can actively, and "freely" pick the state of the switch, and THEN I look for correlations. If I flip the switch to on, I see that the light goes on, and if I flip the switch to off, I see that the light goes off. Assuming that I did this "freely", then I can now CONCLUDE that the correlation between light bulb and switch is a CAUSAL relation: the switch must cause something that lights the light bulb. On the other hand, if with an external battery, I light the bulb, I don't see the switch flipping over. So this is a one-way causal relationship: the switch CAUSES the light bulb to go on.

It could have been different: there could have been a computer that activated electromagnetically a switch, and that also activated through a different circuit, the light bulb. It would have been a 'common cause' scenario, and me flipping the switch "freely" wouldn't make the light bulb light up.

However, a superdeterministic theory would say the following: even if I "freely" flip the switch, and I see a perfect correlation with the light go on or off, this is NO PROOF for a causal relationship between the switch and the light bulb, because there might have been a COMMON CAUSE which made me exactly flip the switch at the right times when that common cause also made the light go on and off. So imagine that the light bulb going on and off is actually caused by, I don't know, some radioactive decay or so, that there is strictly no relationship with the switch, but nevertheless, whatever causes the radioactive decay to happen also happens to influence my brain and makes me flip the switch at exactly the same moment when the light goes on or off. THAT is what a superdeterministic theory tells us: that the correlation I observe between a "freely made" choice and an observed phenomenon does NOT imply a causal relationship from the thing that was determined by the "choice" (flipping the switch) and the observed phenomenon (the light goes on or off), but rather, that my "choice" was exactly in tune with whatever caused really the phenomenon, because it had a common origin.

If I have a superdeterministic theory, I have to work out exactly HOW I am going to make these choices, and demonstrate that my choices are going to be exactly such that a correlation is going to appear AS IF there was a direct causal link. If I don't do that, but I make a "shortcut" to introducing GENUINLY RANDOM choices, then my superdeterministic theory would this time NOT show any correlation - because there IS no causal link between the flipping of the switch and the bulb - there is only a correlation between the choice I made and the light bulb which I did now away with, and hence be in contradiction with the observed correlations.

Now, saying that you COULD eventually do a small-scale calculation with not a brain that makes the "decisions", but a much smaller system - a 3-particle system or something, that might show some hope of being tractable with a computer simulation, doesn't prove ANYTHING. After all, it is very well possible that there IS a small scale correlation with a *particular* simple setup. Imagine for instance that we use a simple periodic oscillator to flip the switch, and that we use an identical oscillator to power the light bulb. Then we WILL find of course a "superdeterministic" correlation without there being a causal link, if the frequencies and phases of both oscillators are identical. But that's simply because the "free choice" made by an oscillator is a simplistic "free choice". It doesn't demonstrate AT ALL that if we use *no matter what mechanism to do the free choosing* we will ALWAYS obtain the same correlation, which is exactly what a superdeterministic theory needs to demonstrate before being able to explain those correlations in a non-causal matter.

 

[PhilDSP]

Well recall that the assumptions in Bell's theorem are that

1) Kolmogorov classical probability axioms are valid.
2) locality is valid (no causal influences can propagate faster than c between two events).
3) causality is valid (future measurement settings are "free" or random variables).

One could only reject locality as is often done, and get a nonlocal HV theory such as the pilot wave theory of de Broglie and Bohm.

Thanks for this clarification. In saying "non-local" about the general pilot wave theory, you mean that in the sense that the system response cannot be determined on the basis of a single instance in time and space don't you?

You're not saying that such a pilot wave must have a "faster than light" transfer of information or energy, are you?

 

[Maaneli]

Thanks for this clarification. In saying "non-local" about the general pilot wave theory, you mean that in the sense that the system response cannot be determined on the basis of a single instance in time and space don't you?

You're not saying that such a pilot wave must have a "faster than light" transfer of information or energy, are you?

By nonlocal I mean that the guiding equation for the particles is given by

dQ/dt = J/P

where J is the quantum probability current, P is the quantum probability density, both deduced from the quantum continuity equation, and Q is the actual position of the particles in space. So this means that the velocity of anyone particle in an N-particle guiding equation depends instantaneously and simultaneously on the positions of all the other particles, due to the fact that the wavefunction defining J and P is a function not in physical 3-space, but in configuration space of dimension R^3N . This nonlocality does not however allow for superluminal signalling (meaning information transfer or observable matter/energy transport for an entangled quantum state). So it is safe from your worries.

 

[PhilDSP]

Okay. Thanks again for being so specific. It's very refreshing to get a straight, very descriptive and usable answer from someone for a change!

 

[Maaneli]

You're welcome. Thanks. Not to sound haughty, but I think this is a subject that most people in this forum are very interested in, but have not studied very carefully, which the reason my answer sounds refreshing to you.

 

[DrChinese]

Well recall that the assumptions in Bell's theorem are that

1) Kolmogorov classical probability axioms are valid.
2) locality is valid (no causal influences can propagate faster than c between two events).
3) causality is valid (future measurement settings are "free" or random variables).

Notice that "realism" is not at all the issue in Bell's theorem, despite the common claim that it is.

Repeating for the sake of completeness: Realism ABSOLUTELY is assumed and critical to Bell's Theorem. Not sure why this is hard for some folks to accept, so let's reference the paper itself: On the EPR Paradox. When Bell says that there is a simultaneous A, B and C (circa his [14] in the original), he is invoking realism. He says "It follows that c is another unit vector...". His meaning is that there if there is an a, b and c simultaneously then there must be internal consistency and there must be an outcome table that yields probabilities for all permutations of outcomes a, b and c that are non-negative. That is where both the Kolmogorov axiom comes into play (also in Bell's []12]), as does EPR style Realism (explicitly formulated here in a way in which Einstein would have to accept).

Bell's conclusion is that if hidden variables are added, they must be non-local. Alternately, QM is complete as is; the EPR paradox is solved with the answer that EPR rejected as "unreasonable" (because Realism is rejected).

 

[Maaneli]

Repeating for the sake of completeness: Realism ABSOLUTELY is assumed and critical to Bell's Theorem. Not sure why this is hard for some folks to accept, so let's reference the paper itself: On the EPR Paradox. When Bell says that there is a simultaneous A, B and C (circa his [14] in the original), he is invoking realism. He says "It follows that c is another unit vector...". His meaning is that there if there is an a, b and c simultaneously then there must be internal consistency and there must be an outcome table that yields probabilities for all permutations of outcomes a, b and c that are non-negative. That is where both the Kolmogorov axiom comes into play (also in Bell's []12]), as does EPR style Realism (explicitly formulated here in a way in which Einstein would have to accept).

Bell's conclusion is that if hidden variables are added, they must be non-local. Alternately, QM is complete as is; the EPR paradox is solved with the answer that EPR rejected as "unreasonable" (because Realism is rejected).

But already discussed that the realism assumption is no different than the realism assumptions made in other physics theorems, and that if you remove realism, it is impossible (or at least inconcievable) to derive an inequality along with the assumptions of locality and causality (and indeed it would become problematic how to define locality and causality without realism) that can be empirically tested and that differs from Bell's. I recall I also challenged you to try and do this. Finally, it is also possible to keep locality, realism, and causality, but to change Kolmogorov's axioms about the measure density on a spherical manifold. For example, see Pitowsky's work:

Resolution of the Einstein-Podolsky-Rosen and Bell Paradoxes
Itamar Pitowsky
Phys. Rev. Lett. 48, 1299 - 1302 (1982)
http://prola.aps.org/abstract/PRL/v48/i19/p1299_1

 

[DrChinese]

But already discussed that the realism assumption is no different than the realism assumptions made in other physics theorems, and that if you remove realism, it is impossible (or at least inconcievable) to derive an inequality along with the assumptions of locality and causality (and indeed it would become problematic how to define locality and causality without realism) that can be empirically tested and that differs from Bell's. I recall I also challenged you to try and do this...

And the full conclusion we came to, quoting yourself a bit further to make it clearer to other readers (such as PhilDSP), was that Realism IS present and a necessary component of Bell's Theorem:

"Indeed the form of realism you generally suggest is an absolutely necessary pin in the logic of the theorem (or any physics theorem for that matter; in fact, that realism assumption is no different than the realism assumptions in, say, the fluctuation-dissipation theorem or Earnshaw's theorem, both of which are theorems in classical physics). But it is completely false to say that realism is necessarily falsified by a violation of the Bell inequalities. There are other assumptions in Bell's theorem, if you recall, which can be varied without making the general mathematical logic of the inequality derivation inconsistent. They are, once again,

1) Kolmogorov classical probability axioms are valid.
2) locality is valid (the propagation speed for causal influences between two events is bounded by the speed of light, c).
3) causality is valid ("future" or final measurement settings are "free" or random variables).

One can drop anyone of these assumptions and it wouldn't falsify realism. Well, if you drop 3) and replace it with a common past hypothesis or a form of backwards causation as Huw Price and others have suggested, then you just have to modify your notion of realism in a particular way (there is a literature on this you know). That's not the same however as saying that realism gets falsified."

So I would completely agree with your statement that violation of a Bell Inequality does NOT imply Realism must be rejected. It could be 1) 2) or 3) above instead. As before, I do not think there is a disagreement between us on this particular point.

A minor nitpick about your 3), Causality: I would change the meaning of causality slightly to be: The future cannot influence the past. If it could (causality violated), it would be possible to draw diagrams where Alice and Bob are causally connected at space-like separated points without there being any non-local influence. I do not believe 3) is mentioned explicitly in Bell's original paper, but I don't think that really changes the sense of Bell's conclusion.

 

[Maaneli]

So I would completely agree with your statement that violation of a Bell Inequality does NOT imply Realism must be rejected. It could be 1) 2) or 3) above instead. As before, I do not think there is a disagreement between us on this particular point.

Yes, OK.

A minor nitpick about your 3), Causality: I would change the meaning of causality slightly to be: The future cannot influence the past. If it could (causality violated), it would be possible to draw diagrams where Alice and Bob are causally connected at space-like separated points without there being any non-local influence. I do not believe 3) is mentioned explicitly in Bell's original paper, but I don't think that really changes the sense of Bell's conclusion.

Yes. In fact the definition that the "future" measurement settings are "random" variables already implies the statement that the "future cannot influence the past". Yes, 3) is not mentioned in Bell's original paper, but of course he discusses it more explicitly in "Free Variables and Local Causality" as well as "La Nouvelle Cuisine".

 

[ueit]

You seem to forget that the particularity of a superdeterministic theory is that the essential correlations found, are due to specific correlations in the CHOICES made by the experimenters because their choices are not "free", and that if we allowed them to be truly random and independent, then the theory would NOT yield the correct results (THAT's what it means to be superdeterministic).

Testing the EPR correlations is not the only way a theory can be verified. A prediction of a complex atomic spectra is good as well.

Let us take a toy example. Let us imagine that I have a switch and a light bulb. When I simply OBSERVE the switch states and the light bulb states, I see a perfect correlation: when the switch is "ON", the light is "ON", and when the switch is "OFF", the light is "OFF". This is an observed correlation, but it doesn't teach me much about any mechanism behind it: are the switch and the light bulb both activated by a common mechanism ? Is the switch causing the light bulb to go on and off ? Is the light bulb causing the switch to go on or off ? Is this just a weird correlation in nature ? Difficult to say.

However, in "normal" deterministic theories, we take it that we can CHOOSE the state of the switch. I can actively, and "freely" pick the state of the switch, and THEN I look for correlations. If I flip the switch to on, I see that the light goes on, and if I flip the switch to off, I see that the light goes off. Assuming that I did this "freely", then I can now CONCLUDE that the correlation between light bulb and switch is a CAUSAL relation: the switch must cause something that lights the light bulb. On the other hand, if with an external battery, I light the bulb, I don't see the switch flipping over. So this is a one-way causal relationship: the switch CAUSES the light bulb to go on.

It could have been different: there could have been a computer that activated electromagnetically a switch, and that also activated through a different circuit, the light bulb. It would have been a 'common cause' scenario, and me flipping the switch "freely" wouldn't make the light bulb light up.

However, a superdeterministic theory would say the following: even if I "freely" flip the switch, and I see a perfect correlation with the light go on or off, this is NO PROOF for a causal relationship between the switch and the light bulb, because there might have been a COMMON CAUSE which made me exactly flip the switch at the right times when that common cause also made the light go on and off. So imagine that the light bulb going on and off is actually caused by, I don't know, some Radioactive Decay or so, that there is strictly no relationship with the switch, but nevertheless, whatever causes the radioactive decay to happen also happens to influence my brain and makes me flip the switch at exactly the same moment when the light goes on or off. THAT is what a superdeterministic theory tells us: that the correlation I observe between a "freely made" choice and an observed phenomenon does NOT imply a causal relationship from the thing that was determined by the "choice" (flipping the switch) and the observed phenomenon (the light goes on or off), but rather, that my "choice" was exactly in tune with whatever caused really the phenomenon, because it had a common origin.

If I have a superdeterministic theory, I have to work out exactly HOW I am going to make these choices, and demonstrate that my choices are going to be exactly such that a correlation is going to appear AS IF there was a direct causal link. If I don't do that, but I make a "shortcut" to introducing GENUINLY RANDOM choices, then my superdeterministic theory would this time NOT show any correlation - because there IS no causal link between the flipping of the switch and the bulb - there is only a correlation between the choice I made and the light bulb which I did now away with, and hence be in contradiction with the observed correlations.

1. You seem to give the "free choice" assumption an overemphasised importance. Hystoricaly, it didn't play an important role (astronomy was the first science to be developed and there were not many experiments with celestial bodies that could be performed in Copernicus' time). In modern times, we have the Big-Bang theory that deals with the universe as a whole. Asking for such a theory to accept "free" experimental imput is logicaly absurd. Does that mean that the evolution of the solar system or the evolution of the universe are not causal? I think not. I don't need a "free-willed" human to produce a non-uniformity in the early universe to accept that such non-uniformities caused galaxy formation. Now, there are situations where laboratory experiments are possible and they greatly reduce the time to develop a theory. But they are not an absolute requirement.

2. One should not start with assumptions that have no scientiffic basis whatsoever. In your example there is a good reason to take the experimenter's choice as a free parameter. We understand pretty well classical physics and we know that two macroscopic, electrical-neutral objects do not interact from a large distance. To propose that something like that happens to the experimenter and the light bulb will require a great conspiracy. On the other hand we do not know the dynamics of the quantum particles. This is the question that must be answered.

3. The argument you give against SD has nothing to do with SD but it is a restatement of Okham's razor. One should not propose a complicated mechanism when it is not required. We understand very well what's happening when a light bulb is switched on. To show you the fallacy I will construct a simillar argument against MWI.

The light bulb, the switch and experimenter are all in a superposition of all possible states. The experimenter does nothing and he is not "free" at all. It so happens that for an unknown reason his consciousness splits so that he only sees the known correlations between the switch and light bulb. I'm sure you can refine this argument so it will be rather devastating against MWI. But it is wrong. The reason we don't propose such explanations is that they are not required here. In the case of EPR they are required because a simple, classical causal chain does not work.

Now, saying that you COULD eventually do a small-scale calculation with not a brain that makes the "decisions", but a much smaller system - a 3-particle system or something, that might show some hope of being tractable with a computer simulation, doesn't prove ANYTHING. After all, it is very well possible that there IS a small scale correlation with a *particular* simple setup. Imagine for instance that we use a simple periodic oscillator to flip the switch, and that we use an identical oscillator to power the light bulb. Then we WILL find of course a "superdeterministic" correlation without there being a causal link, if the frequencies and phases of both oscillators are identical. But that's simply because the "free choice" made by an oscillator is a simplistic "free choice". It doesn't demonstrate AT ALL that if we use *no matter what mechanism to do the free choosing* we will ALWAYS obtain the same correlation, which is exactly what a superdeterministic theory needs to demonstrate before being able to explain those correlations in a non-causal matter.

If the same mechanism works for many different, even if simple setups, it is unlikely that a false, ad-hoc mechanism will work. So I think that a computer simmulation is a perfect way to test the theory. The burden is on you to explain why a human brain is qualitatively different than a random bunch of molecules when QM is concerned, and why such a large scale simullation is required at all.

 

[wawenspop]

I was thinking about your light switch analogy and applying it to entangled particles - i.e. some sort of 'causal correlation' mechanism, that the mathematics does not need, but we apparently do!...
Well, what about the Pauli Exclusion Principle, isn't that somewhat analogous, for say two electrons that *must* have opposite spins to be in the same orbit. I assume the two electrons are completely entangled with each other so that they are not 'individual' electrons. It just seems a more concrete example to consider...

 

[LaserMind]

Paulis Exclusion Principle is simply a bald statement of 'fact' and does not give a mechanism for the behaviour. Likewise entangled particles can be mathematically described using complex matrix analysis, but the 'mechanism' for correlation is again missing. Judging from these threads we are now thinking about mutiple entanglements rather than just between two discrete particles.