Bell's Theorem and Nonlocality

Nice find. The conclusion is well stated. The explanation for the outcome is not a classical hidden variables theory (HVT). I asked what reality would have to be like if quantum mechanics was complete, and the answer would not be a classical one. The question is, will the answer be a different hidden variables interpretation (HVI) that includes deterministic mechanics of continuous wave action in the medium of space on a level of order below what we can currently observe, or some other as yet unknown mechanics? Or are you one who is satisfied to say there is no answer, reality is just spooky?

 

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I am not sure you watched the video closely enough. These questions were referred to. Maybe you just need to watch more of this excellent lecture series.

Spooky is just an emotional response to something that appears contrary to expectations that are drilled into your brain by a lifetime of experience. I have experienced that spooky feeling many times. Here is another part of the lectures that addresses the issues. Continuous wave action in a medium is not going to explain it.

From lecture 3 at the 38 minute mark.
[video=youtube;Ei8CFin00PY]https://www.youtube.com/watch?feature=player_detailpage&v=Ei8CFin00PY#t=2277[/video]

 

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I watched from 1:12:00. I recapped that short bit by acknowledging the summary conclusion at the end. I'm not sure you have read my posts throughout the thread. This is old stuff. The math works. There is no scientific explanation, but I think that explanations for the spookiness will improve over time. I was posing the question about what reality would be like if we were to think that QM was complete, as it stands, but that is not to say that I think it is complete.

Yes, Superposition is the the major thing.

As for continuous wave action in the medium of space, don't forget that I speculate about an undetectable foundational level of order below what would be called the fundamental level of particle physics. It includes the hypothesis that particles are not the same at the foundational level as they are described to be at the fundamental level. There would have to be a whole new level of complexity in order to describe local reality without faster than light communication, I would think.

 

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Did you read my post? I didn't claim there was any meaningful detection problem as far as I was concerned.

Keep us informed.

I'm not clinging to the detection loophole. You seem to have no clue what my position is on all of this. It doesn't look like you read my posts, since you have never acknowledged the content that tells you. Your not knowing my position is easy to solve, and if you do understand it, why not test your understanding by saying what you think my position is, other than I think QM is incomplete.

 

Last I thought I understood your position, it was that the hidden variables interpretation would be ruled out by a loophole-free Bell inequalities test. Such a test, if it produces the same results as existing Bell tests today, would prove that no local deterministic theory can explain certain natural phenomena, falsifying any speculation of that nature. It would demonstrate that if quantum mechanics is incomplete, it cannot be completed through the use of deterministic mechanisms exchanging signals no faster than light. You then stated that until a completely loophole-free Bell test were conducted which closed both the locality and detection loopholes simultaneously and not just one or the other, you would continue to maintain that the hidden variables interpretation doesn't disagree with known science and experiment.

Did I get anything wrong in that synopsis?

 

According to the Heisenberg Uncertainty Principle, particles are always waves to at least some degree. Those waves can be squished down to look like particles with narrow ranges of possibilities, and when describing their mathematical interactions, they interact like particles but do so via every possible path simultaneously.

Or at least the moment of absorption is too quick for us to measure with current techniques, and might be altogether impossible to measure according to certain theories of quantum gravity.

Similar to last question.

Evidence for FTL communication directly contradicts the idea of local reality, and since the form of FTL communication known in experiment isn't of a kind that transmits information which can affect statistical outcomes, it's also necessary to throw out determinism in order to rescue Relativity.

It can go through arbitrarily many slits simultaneously, and it can go through any of the various positions on those slits. It can even occasionally tunnel through the wall spacing between them.

No, the explanation is there in plain sight, it's a predicted consequence of Quantum Mechanics' nonlocality, that certain properties exist in a superposition that can stretch arbitrarily far across the universe until it's collapsed by a measurement. The experiment doesn't "alter the past", otherwise we'd have no way of knowing that anything happened, because we wouldn't have any way of knowing what the original past would be, there'd be an enormous ripple of propagating changes all the way back up to the present. It's not like in Back to the Future where you can change a few things in the past and all that happens is everyone's future haircut and clothing changes and the family now has a dog instead of a cat. The Delayed Choice Quantum Eraser experiment demonstrates for us that nature takes future measurements into account when it causes a wave to collapse.

That's one consequence of the principle, but it actually says something far more precise and significant.

QM replaces cause-and-effect with correlations, i.e. Event B is much more likely to occur at a given time if Event A occurred 10 seconds earlier, otherwise Event B rarely ever happens at all. Regarding position and momentum, you can measure either of them independently to arbitrarily high precision (according to most theories), and you can measure them both simultaneously with reduced precision, but you can never know either of them with exact 100% precision no matter how advanced your technology might be.

Rather you mean if the wavefunction itself doesn't represent the objective reality, then there must be something underlying it. Most physicists today are perfectly happy to accept the wavefunction as the objective reality, since there's no evidence for anything beyond it, it works better than anyone else's theory, and there's a great deal of evidence thanks to Bell et. al. that the wavefunction is in fact an inescapable aspect of nature.

No serious physicist would say that, because QM can't be complete without a working picture of quantum gravity, and because there's nothing wrong with considering wave functions to have their own objective reality.

Just because an idea goes against what you've been taught since you were raised, or it doesn't behave according to the notions you developed about macroscopic objects you've observed with your own eyes and ears, doesn't make it any more "strange" or "spooky" than any of the things you yourself happen to believe.

 

What do you mean there is no scientific explanation. The video was the scientific explanation.

You have this backwards. It should be clear that it is all the classical theories that are incomplete, because they can not possibly account for all the "spooky" behavior.

But did you note that superposition in classical physics does not give the interference cross terms. These cross terms are the source of the spooky behavior. And the reason the cross terms are there is because of the detection process that changes the system from wave nature to particle nature via the normalization (absolute value squared). This detection process reminded me of an RF mixer in electronics. If you have two rf waves in a transmission line they exist in a simple classical superposition. The amplitude of the system at any point is the simple sum of the amplitudes of the two waves. But place a diode in the system and things change. The diode is similar to the absolute value function. With the diode in the system you now get mixing of the frequencies which is a type of interference. Now you have not just the two original frequencies but all the sums and differences of their harmonics. Not to say that an RF mixer acts like a QM, but it is analogous.

All classical explanations exist on our human reality side of the detection process. All complex values have been converted into real number values. Waves have been detected and appear as particles. This is readily apparent in the fact that complex numbers are so alien to our understanding. Even when you invoke a medium, that medium is really a collection of particles or at least it is modeled as a assembly of material/positions, and so exists on our human experiential side of the detection process. We can produce waves in a medium, say wave on the surface of a lake, or a sound in the air, but those things are capable of classical explanations and so are not capable of exhibiting the spooky behaviors. They are made of particles and so have already been detected. If they weren't then we could not experience them.

I have seen your model and its version of superposition. Spherical waves that originate from different positions and the interference pattern is a simple classical addition with no cross terms. Purely classical and therefore can not possible explain the world we know. So yes, superposition is a key feature of QM, but also the wave -> particle detection process that leads to the spooky nature (cross terms) of QM and the violation of Bell's theorem.

yes, yes, yes. Your hobby model crap fest of blah, blah, blah. You have whole threads were you discuss with yourself this weird obsession of your hobby / model. I am surprised they let you treat these forums as a personal blog.

 

I'm not sure if the issue for you is still to falsify my disclaimer that, "My hobby-model is internally consistent to the best of my ability, and it is not inconsistent with known scientific observations and data, stipulating that those observations are understood and explained with the mechanics that they operate by." I never considered falsification of that a likely possibility. You aren't going to be able to do that because, even if your expectation that closing all of the loopholes at the same time comes true, which I doubt, we will still not understand QM or the mechanics that explain it.

I have been past the question of QM being complete or not in my threads for years. I have considered it to be incomplete, and my focus has been on speculating about local reality at a foundational level by including discussions about quantum gravity, and what it would take to make it work from my hobbyist perspective. My speculations and hypothesis are clearly presented as the hobby-model of a layman science enthusiast, and your issue has seemed to be a perceived personal affront. It wasn't intentional, and it is the kind of thing I am use to just letting go of.

I'm staying with you here to flesh out for myself, 1) what the circumstances are in the scientific community now, 2) how we think it would change peoples views when and if the loopholes get closed simultaneously, and 3) what that might mean to the search for quantum gravity. I'm pretty sure you don't think it would end the search, and quantum gravity is the central hypothesis of my model, so my model will still be something I keep evolving for myself.

 

I did notice that on the black board he had written, "Free Pizza". Great way to hold a crowd.

 

As I say, I'm still planning to demonstrate why it's extremely implausible that the existing experimental loopholes could provide a working explanation for the Bell inequality violations seen in the lab. In any case I don't know why you think there never will be a loophole-free test (unless you haven't bothered to look it up), when several groups are planning to conduct such tests within a year or less. A loophole-free-test would very much falsify your speculation, because it would demonstrate that it's impossible to capture all the phenomena of nature and experiment in a theory which restricts communication to the speed of light and requires that certain events and properties are absolutely determined at all times. Although I plan to demonstrate why the existing experiments are already more than enough, once they start conducting loophole free Bell tests, you would have to admit that your hobby model is completely inconsistent with existing data, because there's no local deterministic mechanism that can explain this data, as I've already mathematically demonstrated.

Beyond that, you have no evidence or logical deduction to show that QM requires an underlying deterministic mechanism, whereas all the existing evidence suggests that such a mechanism is neither needed nor likely to exist. All evidence to date, even as it continues to accumulate, points to the wavefunction as objective reality, and probabilistic randomness as an inescapable element of nature.

 

I'm somewhat serious when I say this ... I think that there is something in our human DNA that gives individuals the proclivity to take sides on issues, with the personal confidence that the elements of their position make their side of an issue closer to the "truth" about reality. We have the proclivity to view the other side to just be wrong, because we are convinced we are right.

Maybe that duality of "realistic seeming" positions is what explains the success of humans at solving problems. All problems get looked at from different perspectives by people who are confident that the other side is wrong, and sets out to prove it. If it is in the DNA, I'm saying that it is a good thing, brought about by the chance and randomness in how our DNA came to be structured.

I will view this thread, which we have agreed was both of ours, as if the issue that we are at odds about is one where you are convinced, or will be if the experiments closing all loopholes are successful, that the proofs will mean something that I am convinced they won't mean, even if the loopholes as defined presently in QM are closed. I maintain that eventuality does not make QM complete.

I have not ruled out the possibility, or likelihood from your perspective, that an experiment might show that all of the loopholes can be closed. The measurement loophole might be problematic, so what have you got on closing that?

The good thing is that we don't need the successful experiment that closes all the loopholes, to discuss the nature of reality when and if that occurs. Are you willing to talk about that, or are you so convinced you are right that it isn't worth talking about?

 

And this is why I felt it important to raise this topic. The original purpose wasn't to talk about the various flaws or loopholes allowed in existing Bell/CHSH experiments, it was to talk about the philosophical implications that would be implied by a successful, indisputable loophole-free test such as we may well be seeing in the coming year. I contend that the math derivation I gave illustrating a specific outcome of Bell's Theorem, combined with the associated experimental verification, is sufficient to disprove the very possibility of a local deterministic explanation for the measured outcomes. The assumptions made in that proof were very general and apply to any local hidden variable theory, including any you could ever personally hope to postulate. Do you specifically disagree with the generality of this proof?

A loophole-free Bell inequality violation wouldn't prove that quantum mechanics is complete, but it would conclusively prove that local deterministic laws of physics can't be sufficient to describe nature.

If you're referring to the detection loophole, it was first closed for electrons a few years ago, and then it was recently closed for photons as well, so that the detection efficiencies are near 100% and a failure to detect some of the particles can't account for the experimental results. All that remains is to conduct an experiment in which photons can be reliably transmitted across large distances while still maintaining a high detection efficiency, and several experimental teams around the world now seem to feel confident they're ready to try it out in various different ways.

Given that your objections have seemed personal/philosophical from the start, this is in fact the issue I was hoping more to discuss- the implications of Bell's Theorem and its experimental confirmations, regardless of what few flaws might still briefly remain on the contemporary experimental side.

 

That isn't true. I wish you hadn't resorted to false claims like that. You came after me on my thread with an attitude that I had somehow tried to avoid being proven wrong by your great grasp of QM, and you weren't letting me off the hook, lol. That is a laugh. In my opinion you had, and still have no clue what a Hidden Variables Interpretation is about, and your views about cosmology and QM are narrow minded, hesitant, and without rationale. What gives you incentive to be here is getting me. Which you won't.

You have no conception of the possibilities, and a faulty view of the nature of reality if you think things like "something comes from nothing", or that there are no explanations for the unexplained aspects of QM. There are answers to the questions that are raised by QM, but they won't be found by someone who holds the position that there may be no answers.

I disagree with your conclusion.

I give you credit for getting half of that right by agreeing with me that closing the loopholes does not change anything in regard to QM; it is still incomplete. There are explanations for all of the unexplained aspects of quantum mechanics, and closing the loopholes based on the current incomplete QM leaves the same unexplained observations that make it clear that QM is incomplete.

You are not as well informed as you think you are. I didn't take any exception to the detection loophole. You can consider it closed as far as I'm concerned, even though it isn't yet. QM is still incomplete, and there are still answers as to what might complete it.

The same falsehood you started this post with. You made it personal, I didn't. I just didn't back down because you are not being honest about your motives, and because you have misrepresented, misunderstood, and were ignorant of what I have said.

Let's keep it from being personal. I will, and you should try to be honest about things or we will keep having to breath this bad air. I will wear nose plugs from now on if we keep going, and hopefully you won't be offended by the truth.

Never-the-less, as long as the only thing I ever have to have to do with you is a discussion of QM, and the implications that might follow when and if all the loopholes are closed simultaneously, I'm good.

 

So you're saying that my math proof doesn't show that loophole-free Bell tests can't be explained by local determinism?

 

Would you be comfortable saying that your conclusion is that your math proof shows that loophole-free Bell tests can be interpreted to support the Copenhagen interpretation of QM? I could agree with that.

 

When I asked you this I was going to verify your set up and the math, not that I doubt any of it, but I had some points that I thought you might be able to clear up for me. That is why I quote post #174 for you to see the first question again.

 

I can't say I'm comfortable with making such a statement.

I clearly showed that any theory which only includes local deterministic effects will get a 33%+ correlation outcome regardless of the scheme used to generate the photon pairs and set their polarities. If the correlation results measured by experiment are in the 25% range with high statistical precision, then clearly that 33% threshold is violated and something either nonlocal and/or nondeterministic is happening in the experiment. Which parts of this deduction do you not agree with?

 

There are many different schemes for generating particles with certain properties, the most common one I've read about in the context of Bell tests involves sending a highly filtered beam of photons with a specific frequency into a crystal, and then selecting certain photon pairs produced by the crystal in response. You could produce pairs in which one is always polarized at 20 degrees with respect to the other, or whatever scheme you like, using various optical tricks, and confirm directly in the experimental calibration phase that they have the desired properties (i.e. always correlated on the same axis or on axes with 20 degree separations, or however you like it). The setup makes no assumptions about the Copenhagen interpretation, they're just working with hands-on basics like coherent light sources and optical detectors.

 

I'm not sure we are communicating. Go back to the OP, and look at my #1 in post #174. Explain that in terms of the use of the words "same angle or opposite angle". Are you talking about two different sets of entangled photons, or the two individual photons in the same set?

 

Do you know how many different interpretations there are of QM? Probably over 20. They deal with the nature of reality, local reality or the lack of it, in various degrees. Can you state the generally accepted commonality among the various definitions called the Copenhagen interpretations. Can you differentiate between the Copenhagen interpretations and the Hidden Variables group of interpretations. Can you answer those questions in your own words. The book, which I mentioned to you before, Q is for Quantum" (though dated by now), has a good page that lists them, and then each major group is addressed individually. Have you familiarized your self to the extent that you are aware of that?