Bell's theorem and Harrison's (2006) inequality

[wm]

I'm proposing this new thread as a valid PF-QP contribution; one complying with the relevant rules as I understand them; and the gist of which will be as shown below.

However, I would first like to locate a missing draft, as follows:

Title: Bell's theorem refuted via* Harrison's (2006) inequality?

[Per wm edit:]
wm, I'm interested in your thoughts on

http://www.upscale.utoronto.ca/PVB/Harrison/BellsTheorem/BellsTheorem.html.

I can't find a fault in the logic. Perhaps you can help me out? BoTemp

With the above title and commencement, I had Draft 0.1 in preparation on the PF site when the original thread was closed. The draft was to be presented for critique on that thread to ensure that I had correctly interpreted Harrison's work.

In the interests of fair-play, the draft included the Credo: I could be wrong; just show me where: Because, though the subject theory has been peer-reviewed and published, it is not widely accepted.

The draft had an abstract, introduction, and analysis of a wholly classical experiment which challenged one of Harrison's (2006) assumptions. In so far as I am aware, the draft complied with the relevant PF rules. Much time had been given to making it succinct yet complete.

In that that draft went missing as the thread was being closed, is it possible to somehow recover it?

PS: I dislike rehashing old material. And the above history is given to show that there was nothing offensive in the draft.

Thanks.

* via = through, by way of, by means of, with the aid of, by virtue of. That is, in refuting Harrison's inequality (= Bell's inequality, per Harrison's text), we refute the associated Bell theorem.

 

[Rach3]

The link is broken.

 

[BoTemp]

http://www.upscale.utoronto.ca/PVB/Harrison/BellsTheorem/BellsTheorem.html

PF truncates links when they're displayed. Good idea, but apparently it screws things up for quoting. This link should work.

 

[DrChinese]

I read Harrison's page and didn't pick up a hint that he purports to refute Bell's Theorem. As I understand it, wm lost a draft of something he was writing and it is probably not available any longer.

wm, are you trying to say that you can refute Bell's Theorem as described by Harrison? If so, I might point you to my own proof which is similar and has a structure that makes it easier to discuss (since the proof is marked a-h and is pretty easy to follow). The "negative probabilities" serves as a simple line in the sand between the local realistic vs. quantum mechanical predictions.

 

[RandallB]

wm, are you trying to say that you can refute Bell's Theorem as described by Harrison?
If so, I might point you to my ... has a structure that makes it easier to discuss ...

DrC, don't hold your breath on getting a straight answer in that discussion. I was suckered into a much to long a discussion trying to find some foundation to justify the claim that 'Bell's logic is wrong'!

The claim is based on an idea called “BTR". You can find its origination by checking the “threads started” by wm though clicking on his profile. It is in his thread started before this one from 2004!
I really should have asked him “Where's the beef?” , but then someone a little quicker than I did that two years ago!

I suspect this thread will and should meet the same fate as that one if as I expect there is no clear and detailed explanation of the claim in the next post.

 

[DrChinese]

DrC, don't hold your breath on getting a straight answer in that discussion. I was suckered into a much to long a discussion trying to find some foundation to justify the claim that 'Bell's logic is wrong'!

The claim is based on an idea called “BTR". You can find its origination by checking the “threads started” by wm though clicking on his profile. It is in his thread started before this one from 2004!
I really should have asked him “Where's the beef?” , but then someone a little quicker than I did that two years ago!

I suspect this thread will and should meet the same fate as that one if as I expect there is no clear and detailed explanation of the claim in the next post.

Thanks for the head up, RandallB. I never thanked you properly for pointing out my 1000th post (I had missed it until you pointed it out)... so thanks for that as well.

-DrC

 

[wm]

Bell's theorem refuted via Schneider's (2006) inequality

I read Harrison's page and didn't pick up a hint that he purports to refute Bell's Theorem. As I understand it, wm lost a draft of something he was writing and it is probably not available any longer.

wm, are you trying to say that you can refute Bell's Theorem as described by Harrison? If so, I might point you to my own proof which is similar and has a structure that makes it easier to discuss (since the proof is marked a-h and is pretty easy to follow). The "negative probabilities" serves as a simple line in the sand between the local realistic vs. quantum mechanical predictions.

1. I meant it this way: via = through, by way of, by means of, with the aid of, by virtue of. I've added this clarification to the OP. That is, to be clear: Harrison SUPPORTS Bell's theorem. I DO NOT.

2. THANKS for the citation; I very much appreciate it.

3. I'm happy to tackle your version. The case against it follows readily from the case against the more complex version cited by BoTemp (which I'm committed to addressing first.) <snip>

4. So: Please: From your knowledge of, and involvement with the PF system: Am I to understand that work-in-progress on a thread (ie, a draft post being previewed) is ''dumped'' when the thread is closed? If so, I'll suggest a PF policy change. <snip>

With thanks again, wm [Credo: I could be wrong; just show me where.]

 

[jtbell]

Am I to understand that work-in-progress on a thread (ie, a draft post being previewed) is ''dumped'' when the thread is closed? If so, I'll suggest a PF policy change.

I suggest that you ask about this in the Forum Feedback & Announcements forum, where the person who owns PF and maintains the software may be more likely to see it. I suspect that this is a "feature" of the vBulletin software that PF uses, and not a conscious policy decision.

You probably could have saved your work at the time you got the message that the thread had been closed, by hitting the "back" button on your browser to return to the preview page, then copying the text and pasting it into a word processor or standalone text editor.

When writing a long posting, I try to remember to do it offline in a standalone text editor, then go online and paste it into a message-composition window. I don't have to tie up the phone as long, either, which keeps my wife happy.

 

[wm]

Possible improvement in PF

I suggest that you ask about this in the Forum Feedback & Announcements forum, where the person who owns PF and maintains the software may be more likely to see it. I suspect that this is a "feature" of the vBulletin software that PF uses, and not a conscious policy decision.

You probably could have saved your work at the time you got the message that the thread had been closed, by hitting the "back" button on your browser to return to the preview page, then copying the text and pasting it into a word processor or standalone text editor.

When writing a long posting, I try to remember to do it offline in a standalone text editor, then go online and paste it into a message-composition window. I don't have to tie up the phone as long, either, which keeps my wife happy.

1. Thanks for this; and, yes: I've learned my lesson. With the PF system having so much going for it, I'm happy to move my suggestion to the right place.

2. For completeness here: I will suggest that threads be closed with, say, 3 days notice. (Though the trolls will no doubt mess with it.) That way, drafts or last minute arrangements or summaries (if any) can be finalised; eg, making new arrangements to continue the discussion elsewhere. That also allows for participants to question (on the thread) a possible misconception by the Closer; AND provides some positive closure to those coming late to archived threads. (I know Zz has left the door open ... but my bird has flown.)

3. Re ''back'' button: I did exactly as you say! Believe me! But after the ''invalid forum'' (I think it was) message, another back-hit revealed only an older look-up! (The notification email arrived about 30 minutes later -- due to my mail-scan schedule. It was then I began to understand why my searching was proving futile: the bird had indeed flown.)

With thanks again, and best regards to your happy wife. Long may she be so! wm

 

[ZapperZ]

Please note that I still haven't seen any valid reason that this whole thing should not be done in the IR forum. That forum has been created specifically for this purpose. So unless there's something truly compelling that you can show, this issue that you wish to discuss should go to the IR forum, regardless of your disclaimer that you could be wrong.

And yes, you may consider this as your advance warning before this thread is closed.

Zz.

 

[wm]

Please note that I still haven't seen any valid reason that this whole thing should not be done in the IR forum. That forum has been created specifically for this purpose. So unless there's something truly compelling that you can show, this issue that you wish to discuss should go to the IR forum, regardless of your disclaimer that you could be wrong.

And yes, you may consider this as your advance warning before this thread is closed.

Zz.

Thanks for the warning; but can you help me please: What is it that you need to see?

As I see it: This thread follows from a question re the error in Bell's theorem; BT being judged erroneous in that it fails to agree with experiment. In my view, most rational thinkers would validly draw this conclusion (though the literature is vast).

Thus the most annoying posts (to me) are those that dispute the experiments: I've seen none of that here.

I have the impression the drChinese and BoTemp are serious students of the subject; I certainly am.

So I'm not clear as to your concerns with this thread. And, learning of those concerns from you will educate me, preparatory for other posts.

PS: If this thread closes, am I allowed to add that extensive discussion of these and related subjects will be found at www.watsonics.com[/URL] (which is being revised for a new release in September)?

Thanks

 

[DrChinese]

As I see it: This thread follows from a question re the error in Bell's theorem; BT being judged erroneous in that it fails to agree with experiment. ...

Most people do not believe that Bell's Theorem requires any agreement with experiment. It simply says that the theoretical predictions of Local Reality are incompatible with the theoretical predictions of QM. Since we know the exact circumstances in which they are different (i.e. specific angle settings), it is really hard to see where you can go with this.

 

[ZapperZ]

Thanks for the warning; but can you help me please: What is it that you need to see?

As I see it: This thread follows from a question re the error in Bell's theorem; BT being judged erroneous in that it fails to agree with experiment. In my view, most rational thinkers would validly draw this conclusion (though the literature is vast).

You continue to claim that there is a logical error in Bell theorem. I have yet to see a single paper that supports this claim.

Please note that there's a difference between saying:

(i) Bell theorem is logically wrong

and

(ii) Bell theorem can be violated.

The LATTER is what is being shown in all of the EPR-type experiments, be it bipartite, or multipartite systems employing the CHSH/Zeilinger theorem that have an even stricter condition for Local Realism.

I have seen no support for (i). If you can show substantial peer-reviewed support for such a stand, then it will be considered here. However, if you are thinking of using PF as a "workout pad" for your ideas, then it must be done in the IR forum and not in here.

Zz.

 

[Maaneli]

Zapperz,

This thread could actually be productive, since it turns out that there actually are counterexamples to experiments suggesting that Bell's inequality violations preclude local realism. Moreover, there are the notorious detection loopholes that plague all current experiments. You asked for reputable peer reviewed literature supporting such a claim, so here they are:

T. W. Marshall and E. Santos, Stochastic optics: a local realist analysis of optical tests of the Bell inequalities, Phys. Rev. A, 39, 6271-6283 (1989).

M. Ferrero, T. W. Marshall and E. Santos, Bell's theorem: local realism versus quantum mechanics, Am. J. Phys., 58, 683-8 (1990)

T. W. Marshall, What does noise do to the Bell inequalities, Foundations of Physics 21, 209-219 (1991).

The following series of papers precede the first paper below:

A Local Hidden Variables Model for Experiments involving Photon Pairs Produced in Parametric Down Conversion: Alberto Casado, Trevor Marshall, Ramon Risco-Delgado, Emilio Santos.
http://arxiv.org/abs/quant-ph/0202097

A. Casado, T. W. Marshall, and E. Santos, J. Opt. Soc. Am. B, 14,
494-502 (1997).

A. Casado, A. Fern´andez-Rueda, T. W. Marshall, R. Risco-Delgado,
and E. Santos, Phys. Rev. A 55, 3879-3890 (1997).

A. Casado, A. Fern´andez-Rueda, T. W. Marshall, R. Risco-Delgado,
and E. Santos, Phys. Rev. A 56, 2477-2480 (1997).

A. Casado, T. W. Marshall, and E. Santos, J. Opt. Soc. Am. B 15,
1572-1577 (1998).

A. Casado, A. Fern´andez-Rueda, T. W. Marshall, J. Mart´inez, R. Risco-Delgado, and E. Santos, Eur. Phys. J. D 11, 465 (2000).

A. Casado, T.W. Marshall, R. Risco-Delgado, and E. Santos, Eur. Phys. J. D 13, 109 (2001).

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TVM-46R3K6J-R9&_coverDate=07%2F07%2F1986&_alid=437252268&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5538&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a5d4488093a86628b4933811f3070a9a

http://www.springerlink.com/content/l72g786147n30505/

http://prola.aps.org/abstract/PRL/v66/i11/p1388_1

http://prola.aps.org/abstract/PRA/v46/i7/p3646_1

http://prola.aps.org/abstract/PRA/v30/i4/p2128_1

Regarding all current experimental tests of Bell's inequalities, it turns out that as of 2006, no such experiment has closed the DETECTION LOOPHOLES. A nice review article in wikipedia, with the corresponding references can be read here:

http://en.wikipedia.org/wiki/Loopholes_in_optical_Bell_test_experiments

Also, this fact has motivated Paul Kwiat to get funding for a proposed loophole-free test of Bell's theorem:

http://www.fqxi.org/aw-kwiat.html

So it is fair to say that local realism has still yet to be refuted.

Regards,
Maaneli

 

[ZapperZ]

Zapperz,

This thread could actually be productive, since it turns out that there actually are counterexamples to experiments suggesting that Bell's inequality violations preclude local realism. Moreover, there are the notorious detection loopholes that plague all current experiments. You asked for reputable peer reviewed literature supporting such a claim, so here they are:

T. W. Marshall and E. Santos, Stochastic optics: a local realist analysis of optical tests of the Bell inequalities, Phys. Rev. A, 39, 6271-6283 (1989).

M. Ferrero, T. W. Marshall and E. Santos, Bell's theorem: local realism versus quantum mechanics, Am. J. Phys., 58, 683-8 (1990)

T. W. Marshall, What does noise do to the Bell inequalities, Foundations of Physics 21, 209-219 (1991).

Have you read those papers? NONE of them are "experimental" papers. Santos and Marshall are theorists. They have never done such experiments. All they did is reinterpret the results of someone else's experiments. So these are NOT "counterexamples".

I still have not seen local realists doing these experiments themselves, do not include those necessary substractions, and conclude that their point of view is correct.

Regarding all current experimental tests of Bell's inequalities, it turns out that as of 2006, no such experiment has closed the DETECTION LOOPHOLES. A nice review article in wikipedia, with the corresponding references can be read here:

http://en.wikipedia.org/wiki/Loopholes_in_optical_Bell_test_experiments

Also, this fact has motivated Paul Kwiat to get funding for a proposed loophole-free test of Bell's theorem:

http://www.fqxi.org/aw-kwiat.html

So it is fair to say that local realism has still yet to be refuted.

Regards,
Maaneli

It is just that it is hanging to dear life by a thread.

The "detection" loophole is the often-used lifeline that these people are hanging on to simply because they can point to the fact that we still don't have a 100% efficient photon detector. But I've yet to see anyone argue why there is such an amazing coincidence that all the different types of experiments being done so far have never yielded anything that contradicts QM. And we're talking about everything from using photons, electrons, etc... all the way to bipartite, multipartite experiments. Why is the more stringent requirement GHZ inequality for multipartite entanglement not considered here? There is just way too many compelling evidence that it is simply too unrealistic to attribute all these agreements as simply being "coincidence".

To me, this is as similar as the common complaint we have against the concept of "photons", just because the photoelectric effect can somehow also be explained using classical wave picture. It ignores the amazing progress we have made since then in photoemission spectroscopy, and no attempt has been made to explain the observation of angle-resolved photoemission, resonant photoemission, multiphoton photoemission, etc. using the classical wave theory.

I still want to see somebody perfoms a Bell-type experiment and report that it is consistent with local realism.

Zz.

 

[jtbell]

Someone (I can't remember who, unfortunately) once said something like, "It's dangerous to live inside a shrinking loophole because it may close around your neck before you can wriggle out."

 

[George Jones]

Someone (I can't remember who, unfortunately) once said something like, "It's dangerous to live inside a shrinking loophole because it may close around your neck before you can wriggle out."

I don't know who said it, but I do know that I like it!

I hope I can remember this.

 

[Doc Al]

It's a great line!

 

[Maaneli]

Have you read those papers? NONE of them are "experimental" papers. Santos and Marshall are theorists. They have never done such experiments. All they did is reinterpret the results of someone else's experiments. So these are NOT "counterexamples".

Zapper, yes these papers are theoretical and yes Santos and Marshall are theorists. This does not weaken the validity of their work, nor does it weaken the validity of my statement. Think more carefully about what I said, "there actually are counterexamples to experiments suggesting that Bell's inequality violations PRECLUDE local realism." First off, a counterexample does not have to be experimental. Moreover, this statement does not dispute the fact that these experiments, insofar as they have been carried out, agree with the predictions of QM. It points out that one cannot take this experimental agreement with the predictions of QM, as a refutation of local realism. This is because there is a well constructed and non ad-hoc local realistic theory called stochastic optics, whose predictions agree with these optical tests of Bell's inequality, just as well (and even better in some cases) as the predictions of quantum optics. In other words, stochastic optics is a semiclassical theory that also violates Bell's inequalities. In fact, if I recall correctly, in one of Santos' recent papers, this agreement with experiment is extrapolated and shown even for theoretical detectors of efficiency as high as 80%.

I still want to see somebody perfoms a Bell-type experiment and report that it is consistent with local realism.

As I have just pointed out, ALL the optical tests of Bell's inequalities are consistent with the local realistic formalism known as stochastic optics.

What we really have is a problem of underdetermination between a local realistic theory, and quantum optics, for all these optical Bell-type tests. So, in addition to striving for experiments that close the detection loopholes, we should also identify experiments that allow us to distinguish between these theories. More specifically, we should want to look for predictions that stochastic optics makes, which differs from that of quantum optics. In fact there are such differing predictions. And as of right now, experimental tests of these kind have not been adequately carried out. However, I should point out that I and a Quantum metrology group in Italy, the Carlo Novero lab, have agreed to a collaboration to do exactly this.

So, I have in fact personally corresponded with Marshall and Santos about their work.

The "detection" loophole is the often-used lifeline that these people are hanging on to simply because they can point to the fact that we still don't have a 100% efficient photon detector.

In fact Marshall and Santos argue that you can never have a 100% efficient photon detector because of the stochastic background noise.

It is just that it is hanging to dear life by a thread.

The "detection" loophole is the often-used lifeline that these people are hanging on to simply because they can point to the fact that we still don't have a 100% efficient photon detector. But I've yet to see anyone argue why there is such an amazing coincidence that all the different types of experiments being done so far have never yielded anything that contradicts QM. And we're talking about everything from using photons, electrons, etc... all the way to bipartite, multipartite experiments. Why is the more stringent requirement GHZ inequality for multipartite entanglement not considered here? There is just way too many compelling evidence that it is simply too unrealistic to attribute all these agreements as simply being "coincidence".

To me, this is as similar as the common complaint we have against the concept of "photons", just because the photoelectric effect can somehow also be explained using classical wave picture. It ignores the amazing progress we have made since then in photoemission spectroscopy, and no attempt has been made to explain the observation of angle-resolved photoemission, resonant photoemission, multiphoton photoemission, etc. using the classical wave theory.

Zz.

I agree that if there were only the detection loopholes to dispute these experiments, that would be a much weaker case. But of course we see know that this is not so. However, even then I don't think the experts in this field take the detection loopholes very lightly at all. They don't take these proposed improved experiments as simply refinements on the accuracy of the previous one's, such as the experiments in special relativity or CMB radiation measurements, where the interpretation of the raw data are widely undisputed. In fact, in every paper proposing a refined optical test of Bell's inequality, there is always the emphasis on specifically addressing at least one detection loophole. The titles themselves also always make reference to the detection loopholes or say something like "Towards a loopholes-free test of Bell's inequality". Moreover, as I already pointed out, Paul Kwiat (whom I have also personally spoken with and who acknowledges the criticisms of Marshall and Santos), acknowledges the seriousness of these detection loopholes, which is why he as received funding from the FQX foundation to carry out an experiment to try and close these detection loopholes. Please read his abstract:

http://www.fqxi.org/aw-kwiat.html

With regard to "the more stringent requirement GHZ inequality for multipartite entanglement", to date, there has been no experimental test of the GHZ inequality and so it cannot yet be used as evidence either for or against local realism.

Regards,
Maaneli

 

[DrChinese]

1. So, I have in fact personally corresponded with Marshall and Santos about their work... In fact Marshall and Santos argue that you can never have a 100% efficient photon detector because of the stochastic background noise.

2. With regard to "the more stringent requirement GHZ inequality for multipartite entanglement", to date, there has been no experimental test of the GHZ inequality and so it cannot yet be used as evidence either for or against local realism.

1. Marshall and Santos have a full time job on their hands explaining the many experiments which support the predictions of QM. One problem with their approach: Bell's discovery remains intact! So QM can still never agree with local reality on the theoretical side. So now the burden is on the local realist to make a specific prediction which conflicts with QM. Marshall & Santos don't do this, they instead try to explain why experiments will always agree with QM. That's a funny position for a local realist, to be sure!

2. There are experimental tests of GHZ, such as: Multi-Photon Entanglement and Quantum Non-Locality, Pan & Zeilinger.

Some factions of the local realistic crowd dismiss all counter-examples as failing to meet their "exacting" standards of proof... which only happens to apply to Bell tests.

 

[ZapperZ]

Zapper, yes these papers are theoretical and yes Santos and Marshall are theorists. This does not weaken the validity of their work, nor does it weaken the validity of my statement. Think more carefully about what I said, "there actually are counterexamples to experiments suggesting that Bell's inequality violations PRECLUDE local realism." First off, a counterexample does not have to be experimental.

Yes they do! If you are presenting a counter example of experimental observation, then the counter example HAS to be another experimental observation. If not, you're comparing apples with apes.

With regard to "the more stringent requirement GHZ inequality for multipartite entanglement", to date, there has been no experimental test of the GHZ inequality and so it cannot yet be used as evidence either for or against local realism.

Regards,
Maaneli

Er.. you are way out of date. There have been SEVERAL experiments violating the GHZ inequality, and even one up to 5 entangled particles! Not only that, we even have a recent paper violating the CHSH inequality of an "entangled entanglement"

https://www.physicsforums.com/showpost.php?p=1050283&postcount=8

Zz.

 

[Maaneli]

1. Marshall and Santos have a full time job on their hands explaining the many experiments which support the predictions of QM. One problem with their approach: Bell's discovery remains intact!

As I already said, Marshall and Santos's stochastic optics formalism has done this for ALL optical tests of Bell's inequality. Actually, I don't know about the GHZ experimental test, which I stand corrected on, but one would have to look at Santos' recent papers. At first glance though, I see nothing in the experiment that contradicts a stochastic optical description.

So QM can still never agree with local reality on the theoretical side. So now the burden is on the local realist to make a specific prediction which conflicts with QM. Marshall & Santos don't do this, they instead try to explain why experiments will always agree with QM. That's a funny position for a local realist, to be sure!

No, this is not exactly correct. For all current optical Bell tests, QM and local reality agree on the theoretical side, to the extent that the predictions they make for these experiments are the same. They don't just "try to explain why experiments will always agree with QM." Rather, they explain why all currently done and proposed experiments, as they are designed, do not distinguish between local realistic theories like stochastic optics, and QM. Also, I said this in my last post that they do in fact make specific predictions that differ from QM:

http://arxiv.org/abs/quant-ph/0401003

http://arxiv.org/abs/quant-ph/0202097

http://arxiv.org/abs/quant-ph/0203042


You seem to have a slight misunderstanding of the nature of their work. I encourage you to study some of their papers I cited in my first post.

Some factions of the local realistic crowd dismiss all counter-examples as failing to meet their "exacting" standards of proof... which only happens to apply to Bell tests.

I must disagree. The "local realistic crowd" - i can only speak for Santos and Marshall - has a standard of proof that applies to all of experimental physics. Santos has made the point that for almost 40 years, many people have tried to perform a loophole-free Bell test that also distinguishes between a local realistic theory like stochastic optics, and they have failed. By way of comparison, we may recall that after the proposal by Lee and Yang that parity is not always conserved, this was proved in an uncontroversial (loophole-free) experiment by Wu et al. in less than one year. The same can be said for experimental tests of special relativity. Consequently, it is not so absurd if they conjecture that loophole-free Bell tests are impossible or if the current tests are not conclusive.

And once again, detection efficiency loopholes seem to be taken very seriously by experimentalists in this field such as Kwiat, Aspect, Genovese, - all of whom I have spoken with - etc..

http://www.fqxi.org/aw-kwiat.html

~Maaneli

 

[Maaneli]

Yes they do! If you are presenting a counter example of experimental observation, then the counter example HAS to be another experimental observation. If not, you're comparing apples with apes.

No Zapper. The counter example is not to the experimental observation. It is to the claim that the experimental observation can only be interpreted in one particular way. Experimental raw data is always interpreted to support a particular theory. But if you have more than one theory that is ontologically and mathematically distinct from the others, and that makes the same predictions as the other theories, that are then confirmed by the experiments, then you have a problem with the effectiveness of your experiment in distinguishing between the different theories.

~M

 

[Maaneli]

I should like to bring to attention the following article by Lev Vaidman - a leading authority on quantum measurement theory and frequent coauthor of Yakir Aharonov.

Bell's Inequality: More Tests Are Needed (2001)
According to recent reports, the last loopholes in testing Bell's inequality are closed. It is argued that the really important task in this field has not been tackled yet and that the leading experiments claiming to close locality and detection efficiency loopholes, although making a very significant progress, have conceptual drawbacks.
http://arxiv.org/abs/quant-ph/0102139

 

[QuantunEnigma]

Yes they do! If you are presenting a counter example of experimental observation, then the counter example HAS to be another experimental observation. If not, you're comparing apples with apes.
Zz.

:uhh: I appreciate this thread hanging to dear life and will give my personal opinion in my frame of reference.

You know the EPR's papers did not challenge QM predictions so no real feathers were ruffled during the debate.

wm at [personal theory weblink edited out] do not challenge QM predictions so no real feathers are ruffled during the debate.

wm is a counterexample of apple theory versus apple theory.

Some of the experiments could be completed in a classroom and yield the quantum correlations from a clssical experiment.

Bell in his greatness hoped for a demolition of his theorem. Is that in process done by wm at its site?

CarpeDiem
QuantunEnigma:uhh:

 

[DrChinese]

You seem to have a slight misunderstanding of the nature of their work. I encourage you to study some of their papers I cited in my first post.

I must disagree. The "local realistic crowd" - i can only speak for Santos and Marshall - has a standard of proof that applies to all of experimental physics. Santos has made the point that for almost 40 years, many people have tried to perform a loophole-free Bell test that also distinguishes between a local realistic theory like stochastic optics, and they have failed. By way of comparison, we may recall that after the proposal by Lee and Yang that parity is not always conserved, this was proved in an uncontroversial (loophole-free) experiment by Wu et al. in less than one year. The same can be said for experimental tests of special relativity. Consequently, it is not so absurd if they conjecture that loophole-free Bell tests are impossible or if the current tests are not conclusive.

I am well aware of their work. I would guess that most followers of their work would characterize their position on local reality as extreme (and I don't mean that in a bad way). The fact is, all of their theoretical development (stochastic modeling) is intended for one purpose only: to explain why Bell tests favor QM over LR. Yet the same theory we had in 1928 does this nicely. You may as well spend time explaining why Newton's gravity is correct but experiments support General Relativity, as far as I'm concerned. Where's the beef?

As to loopholes: I think every loophole has been closed individually (fair sampling, locality, etc.). I really don't think there is theoretical justification for the idea that they conspire to be an "open" loophole if they are not all closed simultaneously. The results are always the same, smack on the nose for the predictions of QM.

As you rightly point out: there are respected scientists who are looking for a true "loophole free" Bell test. But I predict that such test is not even possible in principle. In fact, strictly speaking there are no experiments that are truly "loophole free". To be loophole free - to this level of proof anyway - you would need to demonstrate that any and every variable can be modulated simultaneously during the experiment without affecting the results. I don't know of any experiment that meets this criteria.

Of course, we have had our share of discussions on this subject previously on this board. So as not to hijack this thread, I will leave the rest in Zz's capable hands.

 

[ZapperZ]

:uhh: I appreciate this thread hanging to dear life and will give my personal opinion in my frame of reference.

I would strongly suggest you re-read the PF guidelines that you have explicitly agreed to. Pay attention to personal and speculative theories and how PF would handle such a thing. If you wish to continue advertizing your theory (sans your website), please do so in the IR forum per our Guidelines.

Zz.

 

[QuantunEnigma]

I should like to bring to attention the following article by Lev Vaidman - a leading authority on quantum measurement theory and frequent coauthor of Yakir Aharonov.

Bell's Inequality: More Tests Are Needed (2001)
According to recent reports, the last loopholes in testing Bell's inequality are closed. It is argued that the really important task in this field has not been tackled yet and that the leading experiments claiming to close locality and detection efficiency loopholes, although making a very significant progress, have conceptual drawbacks.
http://arxiv.org/abs/quant-ph/0102139

In my frame of reference the start of this thread by wm was about a possible good apple theory and a possible not good apple theory.

I do not see any reference to more tests. I see the opposite.

I concerned that more tests is not the case considered but more theory.

 

[ZapperZ]

I should like to bring to attention the following article by Lev Vaidman - a leading authority on quantum measurement theory and frequent coauthor of Yakir Aharonov.

Bell's Inequality: More Tests Are Needed (2001)

How many more tests do you think has occurred since then? Note that you were not even aware of the several GHZ/CHSH violating experimental evidence.

And no, a "counter example" that you have stated isn't really a counter example. It is a counter interpretation. It isn't a counter example to experiments.

As Dr.Chinese has pointed out, there is not such thing as "loophole-free" experiment, the same way that there are no experiments that "prove" a theory. A theory in physics isn't accepted to be valid by just one experiment, or just one TYPE of experiment. The BCS theory of superconductivity wasn't accepted simply because someone could measure zero resistance on a 4-point probe. I could point a loophole in that single measurement, especially since I've done that experiment a gazillion times. No, something like the BCS theory comes with a slew of not only different resistivity measurement, but also different types of measurements, ranging from magnetic susceptibility all the way to tunneling spectroscopy. While no one experiment can hit a homerun, the compelling evidence in support of such a theory comes from the agreement from the whole wide-ranging experimental evidence.

The same can clearly be said with the Bell-type experiments and the evidence for violation of Local Realism. Results from entanglement of bipartite photons, multipartite photons, charged particles, etc.. all point to the same thing. Each one of these experiments have "loopholes" and "weakness" of their own, but put together, they form a very convincing evidence.

Zz.

 

[RandallB]

, detection efficiency loopholes seem to be taken very seriously by experimentalists in this field such as Kwiat, Aspect, Genovese, - all of whom I have spoken with - etc..

You seem to imply that Kwiat favors Local Reality, I don't think so.
Sure he takes loopholes seriously, he is an experimentalist! And my read of his rather short technical abstract, states his objective for the Grant Funding he has won for UI is:

... a "loophole-free" test of Bell's inequalities, which would unambiguously disprove all local realistic theories and all local hidden variable models for entanglement

That is, to shut the door completely on local reality.

Frankly what I do not understand how simultaneously closing the detection loophole and the timing loophole could do that. Using current results I see no way to fabricate corrections to the widest errors possible caused by those loopholes favorable to Local Reality that would move experimental results far enough to show Local Reality as correct and QM wrong.
Which means I see little point in the experiment he just received funding for.
UI may be happy to get funding but; No matter the results I don't see how this approach can prove anything new, either way.

 

[Maaneli]

I am well aware of their work. I would guess that most followers of their work would characterize their position on local reality as extreme (and I don't mean that in a bad way). The fact is, all of their theoretical development (stochastic modeling) is intended for one purpose only: to explain why Bell tests favor QM over LR. Yet the same theory we had in 1928 does this nicely. You may as well spend time explaining why Newton's gravity is correct but experiments support General Relativity, as far as I'm concerned. Where's the beef?

As to loopholes: I think every loophole has been closed individually (fair sampling, locality, etc.). I really don't think there is theoretical justification for the idea that they conspire to be an "open" loophole if they are not all closed simultaneously. The results are always the same, smack on the nose for the predictions of QM.

As you rightly point out: there are respected scientists who are looking for a true "loophole free" Bell test. But I predict that such test is not even possible in principle. In fact, strictly speaking there are no experiments that are truly "loophole free".

As I had mentioned, the goal for them really is to not only try and close the loopholes, but to also empirically distinguish between two currently indistinguishable interpretations of the optical Bell experiments. Take general relativity for example. There were scalar field theories of gravity which were decisively and unambiguously refuted by the historic experiments of GR. The fact that all these experiments (even the highest efficiency ones) in nearly forty years cannot unambiguously differentiate between local realistic theories like stochastic optics, in the way that the experiments of GR could for scalar field theories, implies that the question of whether local realism contradicts nature is still unresolved. It also implies a problem with the methodology of these experiments using PDC and atomic cascade. Again, the experimentalists in the field like Kwiat, Aspect, and Genovese, who strive for loop-hole free tests, are aware of the work of Santos and Marshall and are aware that the optical experiments thus far do not differentiate quantum optics from their stochastic formalism.

To be loophole free - to this level of proof anyway - you would need to demonstrate that any and every variable can be modulated simultaneously during the experiment without affecting the results. I don't know of any experiment that meets this criteria.

No, I don't quite agree with this. To be "loophole free" you would need to demonstrate that there are no variables in these experiments that can be used to locally correlate "photon" pairs, such as in stochastic optics. In other words, you would have to remove the possibility of the experimental results being explained by a local realistic theory (It is critical to understand this point). That would mean you would have to remove the local hidden variables of the stochastic optical theory, which is the zero-point noise. This has not been possible with the current experiments.

In fact, for practical and theoretical reasons, experimentalists may never be able to remove certain loopholes, such as the detector efficiency loophole simply because stochastic noise would be impossible to remove from any of these experiments. It is this stochastic noise which causes the accidental dark counts and what inherently limits detector efficiences from reaching 100%. Moreover, it is stochastic noise that correlates photon pairs.

Thus, this will always allow these particular optical Bell tests to be consistent with local realistic theories like stochastic optics. And that's where the problem lies. If we really want to test locality, at this point it will do us better to carry out experiments testing the different predictions of stochastic optics versus quantum optics (see the three papers in my previous post), rather than just continuing to refine the efficiency of the traditional Bell type tests, which a priori cannot distinguish stochastic optics from QM.

And no, a "counter example" that you have stated isn't really a counter example. It is a counter interpretation. It isn't a counter example to experiments.

That's just a game of semantics. I didn't say it my argument was a "counter example to experiments". Besides, that statement is logically ambiguous. Once again I said I had a counter example to the standard interpretation of the experiments. A local realistic counter interpretation is in fact a counter example to the claim that there are no local realistic theories that are compatible with the results of these experiments. I don't know what tells you that a counter example HAS to be defined as a counter experiment. Your epistemology is a bit mangled.

The experiments with charged particles have other issues associated with them. An example is problems with tests of local realism by CP-violation parameters of K^0 mesons:

http://arxiv.org/abs/quant-ph/0501039

 

[Maaneli]

You seem to imply that Kwiat favors Local Reality, I don't think so.

Neither do I, and I never implied that he favors local reality. I was pointing out that he acknowledges the problems with all current experiments.

 

[ZapperZ]

In fact, for practical and theoretical reasons, experimentalists may never be able to remove certain loopholes, such as the detector efficiency loophole simply because stochastic noise would be impossible to remove from any of these experiments. It is this stochastic noise which causes the accidental dark counts and what inherently limits detector efficiences from reaching 100%. Moreover, it is stochastic noise that correlates photon pairs.

I disagree. There is 100% detection efficiency when you use entangled electrons, for example. So one can remove such detection loophole using charged particles. However, these experiments have other shortcomings. Yet, each one of them, having different TYPES of loopholes, still arrive at the identical conclusion! By itself, each of these experiments cannot make a convincing argument. But taken together, they portrait a very strong argument towards violation of local realism. You would have to argue for unrealistic coincidence for each of these different types of experiments to ALL point to the same conclusion.

And speaking of photon detection loophole and efficiency, how come Marshall and Santos have never applied their methodology to arrive at the identical results from photoemission spectroscopies? After all, this IS the essence of photon detection - the liberation of an electron to signify the photon's presence, leading to a cascade in a PMT or a simple current. There is no way to check if such stocastic idea is valid when it hasn't been applied to something that we KNOW for sure produces a valid result. Since the whole issue here is photon detection via an explicit photoemission process under a background of a potential difference, why haven't we seen this applied to a laboratory tested photoemission result? Show that it can also produce those band structures that we have observed.

Zz.

 

[Maaneli]

I disagree. There is 100% detection efficiency when you use entangled electrons, for example. So one can remove such detection loophole using charged particles. However, these experiments have other shortcomings. Yet, each one of them, having different TYPES of loopholes, still arrive at the identical conclusion! By itself, each of these experiments cannot make a convincing argument. But taken together, they portrait a very strong argument towards violation of local realism. You would have to argue for unrealistic coincidence for each of these different types of experiments to ALL point to the same conclusion.

This is true about entangled electrons. However I am strictly speaking of the detection of light. Stochastic optics has not yet been applied to electrons. The reason for this is that we have no semiclassical approximation of the electron. There are some ideas along this line in the field of stochastic electrodynamics and other foundational work in classical electrodynamics. But they are too speculative. So I can't argue for a counter interpretation here.

Isn't it interesting though that the most accurate formulation of classical electrodynamics and optics - stochastic electrodynamics and optics - which derives and correctly take into account the contributions of the classical zero-point fields, can locally and realistically account for all the known nonlocal quantum optical phenomena, that is, nonlocal phenomena with light. So we don't know how far this approach can be taken or if it can treat and account for ALL nonlocal phenomena in quantum optics. Now one can ask whether it is worth one's time and energy to investigate these kinds of local realistic extensions to physics. Indeed it would be understandable to argue not to. But one could have said the same thing before the work of Marshall and Santos. And, for me, though I have no definite convictions either way, the surprising success of a local realistic description of the nonlocal behavior of light, whose stochastic local 'hidden variables' emerge as a required condition of classical fluctuating charges and fluctuating radiation in electrodynamic equilibrium, is a very interesting concidence and to me suggests something possibly deeper, namely, that a local realist description might be plausibly possible for all of quantum optics. So I do believe that these continued experiments and theoretical developments of the stochastic optical work of Santos and Marshall are worth investigating - and by that, I mean experimental testing, theoretical development, and constant comparison against the well established quantum optical theory of light.

And speaking of photon detection loophole and efficiency, how come Marshall and Santos have never applied their methodology to arrive at the identical results from photoemission spectroscopies? After all, this IS the essence of photon detection - the liberation of an electron to signify the photon's presence, leading to a cascade in a PMT or a simple current. There is no way to check if such stocastic idea is valid when it hasn't been applied to something that we KNOW for sure produces a valid result. Since the whole issue here is photon detection via an explicit photoemission process under a background of a potential difference, why haven't we seen this applied to a laboratory tested photoemission result? Show that it can also produce those band structures that we have observed.

Zz.

In fact they have applied their methodology to detectors:

http://arxiv.org/abs/quant-ph/0207073

http://arxiv.org/abs/quant-ph/0206161

http://arxiv.org/abs/quant-ph/9711046
(Please excuse or disregard the extremity of the title. Section five emphasizes the theory of detection).

~Maaneli

 

[ZapperZ]

This is true about entangled electrons. However I am strictly speaking of the detection of light. Stochastic optics has not yet been applied to electrons.

And this is WHY I said earlier that it isn't convincing. The QM description has no such need to redevelop something new because the identical phenomnena governs all of them.

In fact they have applied their methodology to detectors:

http://arxiv.org/abs/quant-ph/0207073

http://arxiv.org/abs/quant-ph/0206161

http://arxiv.org/abs/quant-ph/9711046
(Please excuse or disregard the extremity of the title. Section five emphasizes the theory of detection).

~Maaneli

You didn't understand what I asked. I asked them to simulate the results of PHOTOEMISSION SPECTROSCOPY, not "detectors". Detectors make USE of the detail, intricate mechanism of photoemission. So try to simulate something we already know and can verify very well - photoemission spectroscopy. Try pick any PES results on, oh, let's say silicon, and show me that they could produce the same result. And this should be simple, because I haven't required YET for them to show how they could obtain a result from ARPES measurement.

Zz.