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

  1. Aug 8, 2006 #1

    wm

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    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?
    http://www.upscale.utoronto.ca/PVB/Harrison/BellsTheorem/BellsTheorem.html.
    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.
     
    Last edited: Aug 9, 2006
  2. jcsd
  3. Aug 8, 2006 #2
    The link is broken.
     
  4. Aug 9, 2006 #3
  5. Aug 9, 2006 #4

    DrChinese

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    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.
     
  6. Aug 9, 2006 #5
    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.
     
  7. Aug 9, 2006 #6

    DrChinese

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    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
     
  8. Aug 9, 2006 #7

    wm

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

    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.]
     
    Last edited: Aug 9, 2006
  9. Aug 9, 2006 #8

    jtbell

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    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. :wink:
     
  10. Aug 9, 2006 #9

    wm

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    Possible improvement in PF

    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
     
  11. Aug 10, 2006 #10

    ZapperZ

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    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.
     
  12. Aug 10, 2006 #11

    wm

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    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 (which is being revised for a new release in September)?

    Thanks
     
  13. Aug 10, 2006 #12

    DrChinese

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    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.
     
  14. Aug 10, 2006 #13

    ZapperZ

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    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.
     
  15. Aug 21, 2006 #14
    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/scienc...serid=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
     
  16. Aug 22, 2006 #15

    ZapperZ

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    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.

    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.
     
  17. Aug 22, 2006 #16

    jtbell

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    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."
     
  18. Aug 22, 2006 #17

    George Jones

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

    I hope I can remember this.
     
  19. Aug 22, 2006 #18

    Doc Al

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    It's a great line!
     
  20. Aug 22, 2006 #19

    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%.


    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.


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



    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 recieved 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
     
  21. Aug 22, 2006 #20

    DrChinese

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    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.
     
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