why is superdeterminism not the universally accepted explanation of nonlocality?


by jadrian
Tags: accepted, explanation, nonlocality, superdeterminism, universally
ThomasT
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#235
Mar3-12, 04:50 AM
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Quote Quote by jadrian View Post
i really like ur posts, and you obviously have one hell of a bat upstairs, which is good to know theres some 150s and 160s leaning towards determinism.
You mean like "bats in the belfry"? Hopefully, we can see this through to at least a somewhat satisfying conclusion for everybody. Like, maybe we'll actually clarify something.

EDIT: I should add that there are some quite knowledgeable people who contribute to these sorts of threads. Not the least of which is DrChinese. His web site is a great resource.

Also, by the way, I noticed in passing some references to 'free will'. I don't think it has anything to do with any of this. There are subtle considerations, but free will isn't one of them, imho. It's one of those things, like superdeterminism, that can muddy up the real issues.
jadrian
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#236
Mar3-12, 04:57 AM
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Quote Quote by ThomasT View Post
@ lugita15,

The exchange between you and I got a little off track. Which was my fault, and I apologize for not taking the time to sort it out properly. Below I'll comment in reference to an exchange between you and zonde, and hopefully any misunderstanding will be clarified.


I think that there's some step or steps in the LR line of reasoning which then lead(s) to the logically necessary conclusion that the correlation between θ and rate of coincidental detection should be linear. But I don't think it's the prediction of perfect correlation at θ = 0°. After all, QM predicts the same thing as LR at θ = 0°, but wrt all θ the QM and LR correlations are different. So it seems that we can't attribute that difference to the prediction of perfect correlation at θ = 0°.



I already agree with this, and have said so many times in this thread. But you're not then done. This is where the assessment of the necessity of a local superdeterministic model of quantum entanglement begins.


I agree that the answer is no.

Ok, now I disagree.

This is the basis of both the QM and LR treatments, but I would argue that, given this perfect correlation (ideally) at θ = 0°, one is not then forced to believe in a linear correlation wrt all values of θ. After all, the QM treatment leads to a nonlinear correlation wrt all θ.

So, given what we do agree on, wouldn't the first step in assessing the applicability of the concept of superdeterminism wrt generating the simplest and clearest possible understanding of why BIs are violated have to do with identifying any and all points in the LR reasoning which lead to the prediction of a linear correlation between θ and rate of coincidental detection?


Ok, I think I see one source of our misunderstanding. I'm not a local realist. That is, I don't think that a viable LR model of quantum entanglement is possible.

But I am a local determinist. I think that both of these assumptions, locality and determinism, are supported by ample empirical evidence. They seem to be the basis of our everyday navigations through our shared reality. And they seem to be the basis for doing physical (essentially mechanistic) science. As far as I can tell, the assumptions of nonlocality and indeterminism arise, more or less ad hoc, from our inability to make viable LR models of quantum entanglement and our inability to predict certain quantum experimental phenomena.

I'm going to stop here, but will pick up, eventually, where I left off, with a brief exposition of the local deterministic approach to understanding quantum entanglement, and then tying it into the thread question. The focus will eventually be on identifying the precise elements in the standard LR formulation (line of reasoning) which are at odds with what's presumably (according to a local deterministic view) occuring in the underlying reality, and how the encoding of certain elements contrary to that view into an LR formalism, and a Bell inequality, necessarily entails the violation of BIs.

Then the question will be: what, exactly, has been proven, and does our understanding of BI violations necessarily warrant the assumption of superdeterminism in order to maintain a local deterministic view of our universe?

Note: It's important to keep in mind that the formal requirement, local realism, is not equivalent to the philosophical orientation, local determinism. The former having to do with what's required to render a model of quantum entanglement explicitly local or explicitly realistic (without any ad hoc associated nonlocal mechanisms or assumptions), or, as with Bell's formulation, both -- and the latter having to do with assumptions about the way our world is, based on extant empirical observations.
also want to say i dont think local realism is a necessary platform for determinism.
ThomasT
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#237
Mar3-12, 05:00 AM
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Quote Quote by jadrian View Post
also want to say i dont think local realism is a necessary platform for determinism.
Then we agree on that. I'd even go a bit further and say that local realism isn't a necessary platform for local determinism. One is a set of formal requirements (restrictions on formalism), the other is a philosophical orientation based on our experience.
jadrian
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#238
Mar3-12, 05:09 AM
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Quote Quote by ThomasT View Post
Then we agree on that. I'd even go a bit further and say that local realism isn't a necessary platform for local determinism. One is a set of formal requirements (restrictions on formalism), the other is a philosophical orientation based on our experience.
also as nonlocal interactions will be considered predetermined, i think this is the best way for relativity to reconcile with qm
ThomasT
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#239
Mar3-12, 05:27 AM
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Quote Quote by jadrian View Post
also as nonlocal interactions will be considered predetermined, i think this is the best way for relativity to reconcile with qm
This is a bit vague. And I think that QM and SR have already been reconciled in the form of quantum field theory. Which I'm not fluent in.

By the way, I appreciate your posts, but try to stay on topic.

I'm going to go back and read the preceding several pages because it seems that you've had a lot to say. Give me at least 30 minutes. And if there's any point that you'd like to make that you think is important to the thread topic that you haven't already made, then let's hear it.

EDIT: jadrian, my apologies. I recall now that you're the original poster (the OP, which can refer to original poster, or original post).

Well then, perhaps you might synopsize your assessment of the thread thus far ... and we'll take it from there.
jadrian
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#240
Mar3-12, 05:42 AM
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Quote Quote by lugita15 View Post
Whatever you think of Bell tests, do you think you can reproduce the result of a Bell test using billiard balls? How would you do so?
u cant rule out the possibility of a model that could
jadrian
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#241
Mar3-12, 05:48 AM
P: 143
Quote Quote by ThomasT View Post
This is a bit vague. And I think that QM and SR have already been reconciled in the form of quantum field theory. Which I'm not fluent in.

By the way, I appreciate your posts, but try to stay on topic.

I'm going to go back and read the preceding several pages because it seems that you've had a lot to say. Give me at least 30 minutes. And if there's any point that you'd like to make that you think is important to the thread topic that you haven't already made, then let's hear it.

EDIT: jadrian, my apologies. I recall now that you're the original poster (the OP, which can refer to original poster, or original post).

Well then, perhaps you might synopsize your assessment of the thread thus far ... and we'll take it from there.
wear a poncho its a bit of a ****storm. i learned alot along the way but its hard for me to blindly accept assertations from someone who thinks he is alive in the traditional sense and believes he chooses his future as if isolated from very basic laws of physics and the universe itself
ThomasT
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#242
Mar3-12, 05:54 AM
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Quote Quote by jadrian View Post
wear a poncho its a bit of a storm. i learned alot along the way but its hard for me to blindly accept assertations from someone who thinks he is alive in the traditional sense and believes he chooses his future as if isolated from very basic laws of physics and the universe itself
Not sure what this means or what it's in response to.
ThomasT
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#243
Mar3-12, 05:58 AM
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Quote Quote by lugita15
Whatever you think of Bell tests, do you think you can reproduce the result of a Bell test using billiard balls? How would you do so?
Quote Quote by jadrian View Post
u cant rule out the possibility of a model that could
If you used billiard balls, then it wouldn't be a Bell test. You could model any billiard ball test using classical mechanics.
jadrian
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#244
Mar3-12, 08:15 AM
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Quote Quote by ThomasT View Post
Not sure what this means or what it's in response to.
dr chineses assertions
ThomasT
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#245
Mar3-12, 08:29 AM
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Quote Quote by jadrian View Post
dr chineses assertions
Ah. Ok, still not sure about it. But that's ok. A bit off-topic. Of course it's your topic, so I guess you can swerve a bit now and then, so to speak. Not sure about the rules on that.

Anyway, yeah, I agree that it's generally not a good idea to blindly accept assertions from anybody, though, in my experience, DrC's assertions are generally pretty good. But nevertheless check them out.
jadrian
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#246
Mar3-12, 08:49 AM
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Quote Quote by ThomasT View Post
Ah. Ok, still not sure about it. But that's ok. A bit off-topic. Of course it's your topic, so I guess you can swerve a bit now and then, so to speak. Not sure about the rules on that.

Anyway, yeah, I agree that it's generally not a good idea to blindly accept assertions from anybody, though, in my experience, DrC's assertions are generally pretty good. But nevertheless check them out.
yeah i didnt understand the part 2 of superdeterminism when i made this thread. i should have just said determinism
metacristi
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#247
Mar3-12, 01:21 PM
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Quote Quote by jadrian View Post
from my thinking nonlocality and entanglement are never a problem because in a totally determinstic universe, the information about what is going to be instantaneously tranferred from a to b is already known to the universe. we may not be in block time but the universe acts as if it were. this is the first thing ive come across that agrees with my resolution of instantaneous info transfer.

even tho i personally believe that entanglement is basicly a zero sum static, and it is essentually noneffectual on the universe, just something we have to live with, but does not violate relativity because the information does not have any effect on anything anywhere. why is this not mainstream? do most people want to live in an undetermined future, thinking its closer to free will?

The idea that Nature conspire somehow to produce the results observed in Aspect, Gisin, Zeilinger and so on type of experiments (which do not necessarily involve strong determinism but only the existence of some pre-determinism at Planck level, no counterfactual definiteness in the experiments) is still a solution to the problem no doubt. And it is by no means above science. Unfortunately at this time this program is far from being even remotely close to the alternative programs which accept counterfactual definiteness in the experiments.

But this does not mean that it cannot become progressive in the future. We must remain open to this. In my view this is the best decision at this moment in time, inventing another 'no-go theorem' in this case (extremely shaky anyway) is at least counter-productive (and which could even prove to be an error far worse than von Neumann's 'proof' that hidden variables are impossible). Happily some leading scientists take it seriously, among them t'Hooft:

http://arxiv.org/abs/hep-th/0104219
http://arxiv.org/abs/quant-ph/0212095
http://arxiv.org/abs/hep-th/0105105
lugita15
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#248
Mar3-12, 03:03 PM
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Quote Quote by ThomasT View Post
@ lugita15,

The exchange between you and I got a little off track. Which was my fault, and I apologize for not taking the time to sort it out properly. Below I'll comment in reference to an exchange between you and zonde, and hopefully any misunderstanding will be clarified.
OK, and I think one thing that leads to misunderstanding is a terminology issue. You're using local determinism to refer to a philosophical stance, while you're using local realism to refer to a particular formal model which tries to implement this philosophical stance. I'm using both local realism and local determinism, pretty much interchangably, to refer to the philosophical stance, not to any formal model or formal constraint. So just keep that in mind when reading my posts.
I think that there's some step or steps in the LR line of reasoning which then lead(s) to the logically necessary conclusion that the correlation between θ and rate of coincidental detection should be linear. But I don't think it's the prediction of perfect correlation at θ = 0°. After all, QM predicts the same thing as LR at θ = 0°, but wrt all θ the QM and LR correlations are different. So it seems that we can't attribute that difference to the prediction of perfect correlation at θ = 0°.
OK, let me try once more to show you how the logic of Bell's theorem forces any local determinist to disagree with at least some of the predictions of quantum mechanics.

1. Pretend you are a local determinist who believes that all the experimental predictions of quantum mechanics is correct.
2. One of these experimental predictions is that entangled photons are perfectly correlated when sent through polarizers oriented at the same angle.
3. From this you conclude that both photons are consulting the same function P(θ). If P(θ)=1, then the photon goes through the polarizer, and if it equals zero the photon does not go through.
4. Another experimental prediction of quantum mechanics is that if the polarizers are set at different angles, the mismatch (i.e. the lack of correlation) between the two photons is a function R(θ) of the relative angle between the polarizers.
5. From this you conclude that the probability that P(-30)≠P(0) is R(30), the probability that P(0)≠P(30) is R(30), and the probability that P(-30)≠P(30) is R(60).
6. It is a mathematical fact that if you have two events A and B, then the probability that at least one of these events occurs (in other words the probability that A or B occurs) is less than or equal to the probability that A occurs plus the probability that B occurs.
7. From this you conclude that the probability that P(-30)≠P(30) is less than or equal to the probability that that P(-30)≠P(0) plus the probability that P(0)≠P(30), or in other words R(60)≤R(30)+R(30)=2R(30).

Which of these steps do you disagree with and why?
I already agree with this, and have said so many times in this thread. But you're not then done. This is where the assessment of the necessity of a local superdeterministic model of quantum entanglement begins.
But you're only agreeing that some particular formal model does not agree with the predictions of QM. In my 7-step argument above, I am trying to prove that ANY believer in local determinism MUST disagree with some of the predictions of QM.
Ok, now I disagree.

This is the basis of both the QM and LR treatments, but I would argue that, given this perfect correlation (ideally) at θ = 0°, one is not then forced to believe in a linear correlation wrt all values of θ. After all, the QM treatment leads to a nonlinear correlation wrt all θ.
The reason that quantum mechanics is able to have both perfect correlation at identical angles and nonlinear correlations as a function of angle is that QM does not say that the decision about whether the photon goes through the polarizer or not is predetermined by a function P(θ). In particular, if one polarizer is turned to -30 degrees and the other polarizer is turned to 30 degrees, quantum mechanics doesn't believe that the photons have a definite polarization at 0 degrees, and thus QM does not believe in P(0) which is essential for the proof above.
Then the question will be: what, exactly, has been proven, and does our understanding of BI violations necessarily warrant the assumption of superdeterminism in order to maintain a local deterministic view of our universe?
Yes, it does. The proof above decisively shows that in any local determinist universe, we must have R(60)≤2R(30). But the way superdeterminism gets around this is by saying that it is impossible to get accurate measurements of R(30) and R(60), because the experiment is rigged: since whatever is controlling the measurement decision interacted in the past with the (ancestors of) the entangled photons, the experimenters are selecting the angles just right (because the particles controlling them know the exact details of the function P(θ) for the entangled pair of photons) so that it appears that R(60)>2R(30).

That's why I said the following to you earlier in this thread:

"So here's another way to put it: An ordinary local realist theory just assumes that particles which are considered entangled according to QM must have had local interactions in the past which is determining their EPR-type nonlocal correlations today. But a local superdeterminist theory assumes that a particle must have interacted in the past with not only those that are entangled with it according to quantum mechanics, but also other particles which quantum mechanics would say have no connection with it. This is how a local superdeterministic theory would be able to produce Bell-type nonlocal correlations."

And again, remember that when I say local realism I mean the philosophical stance you call local determinism.
lugita15
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#249
Mar3-12, 03:11 PM
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Quote Quote by jadrian View Post
youre pretty much proving my point. the info is essentially static until reconciled by the experiment, which will always occur slower than c.
Yes, the local information will always show boring 50-50 results, and it's only when you make a slower-than-light comparison of the data that you are able to see the nonlocal correlation.
lugita15
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#250
Mar3-12, 03:13 PM
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Quote Quote by jadrian View Post
if the nonlocal stuff cannot have ftl effects on its surroundings then it can be regarded as not existing.
Well, it depends on your terminology. It's as if the faster-than-light stuff has effects, but those effects cannot be discovered until you do slower-than-light communication or travel.
lugita15
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#251
Mar3-12, 03:54 PM
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Quote Quote by jadrian View Post
yeah i didnt understand the part 2 of superdeterminism when i made this thread. i should have just said determinism
So now that you understand what the part 2 is (conspiratorial initial conditions), do you consider yourself a nonlocal determinist like the Bohmians, as opposed to a superdeterminist?
DrChinese
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#252
Mar3-12, 04:42 PM
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Quote Quote by lugita15 View Post
Duh, the lasers can see the entire future of the universe and know which photons will later be considered entangled according to QM. Duh, it changes their undetectable hidden variables, which don't have any effect on the particles until an entanglement experiment is done.

DrChinese, let out your inner conspiracy theorist!


I guess I just don't have what it takes... I feel so inadequate.


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