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Finding Einstein’s Hidden Variable

  1. Aug 18, 2007 #1
    Einstein and a few others since the 1935 EPR paper took the position that defining in knowable terms a hidden variable would show Quantum Mechanics to be incomplete. In that sense proving Quantum Mechanics wrong as “THE” theory of physics, regardless of how accurate and useful the predictions at the atomic level might be. However for a Einstein’s unknown variable to be complete such HV needs to be clearly defined and demonstrate an ability to resolve “Weird Actions at a Distance” as nothing more than Local and Realistic results of detriment Hidden Variables.

    Debating the idea of an Unknown Hidden Variable is not new philosophically or scientifically. I wish to keep this thread scientific. Therefore, for proposes of this thread, Detriment Variables, as expected by Einstein, DOES NOT require or establish “determinism” from the past or into the future. We only require that once a variable is established by some interaction on an entity (Particle or Photon), it retains pertinent detriment values as it travels until changed by some contact such as “measurement”. So, for fans of determinism please keep input on that philosophy in other threads, preferably in the Philosophy Forum. I’d like to also assume that readers here already understand the principles contained in the Bell Theorem, so for those not up to speed on EPR & Entanglement I recommend reviewing the links at: DrChinese-BellTheorum I consider DrChinese the best Science Advisor on our forum when it comes to understanding Bell Theory / QM Entanglement issues.

    Many experiments produce observations (e.g. interference patterns) that imply Quantum Weirdness or Hidden Variables must be in play. But only one offers the opportunity to falsify or verify the HV idea. Bell correlation tests by applying the Bell Theorem have to date falsified the idea of an Unknown Einstein Hidden Variable. Yet Local Realists still remain; unconvinced by Bell Experiments, and experimentalist still search for ways to provide a test that will close “loopholes” and eliminate any remaining doubts about the Non-Local/Realistic nature of reality.

    Science should be able to find a way to conclusively decide between “Local” vs. “Non-Local” reality. Rather than look for flaws in QM or Bell tests, I suggest we take a closer look at flaws in the Local Realist claims of errors in Bell tests matching QM predictions that cannot be matched by a Local Variable. Attached is a chart of correlation plots showing QM & LR (Local Realist) predictions. The problem we have is there are TWO predictions made by LR’s, one with a 25% min. and a 75% max. The other is a straight line from 0% to 100% that comes close possibly within “Measurement Loophole Errors” for experimental measurements that match the QM prediction.

    There can never be a common understanding between LR’s and non-local theories if something a simple as clearly defining the correct expectation of a Local Realist. Therefore this must be our first step, defining clearly what the LR correlation predictions should be based on known classical science. Building such a clear definition that can be confirmed experimentally is worth separating it into the nest post for this thread.

    ©2007 Randall B

    Attached Files:

  2. jcsd
  3. Aug 18, 2007 #2
    Defining the Local Realist Known Variables

    The maximum correlation coverage in a Photon Polarization correlation experiment to satisfy “Bell Inequities” is the straight line from 0% to 100% as shown in the Opening Post diagram. However, I see no justification for a Local Realist to claim that line as a prediction of LR, and challenge any LR to produce an explanation that could justify it. Additionally, I believe we can define an experiment, that can realistically be preformed, to shown that the 25% to 75% line is the best a LR can expect based on known classical science. By modifying the traditional Photon Entanglement Experiment using PDC (Parametric Down Conversion) Malus' Law of polarization intensities to define the LR expectations. Reference the attached diagram of a PDC test with FOUR test areas instead of TWO test areas normally placed where the H (horizontal) & V (vertical) polarized rings of light intersect to define A (Alice) & B (Bob) test areas. The results from combining A1 & A2 when combined should total the same as what will be found at the original A test area at the left side intersection. Note based on how we know PDC works paired photons created with those found at A1 are certain to be found at B1, likewise at fro A2 & B2. Also, since we are the experiment specifically so that only one photon at a time is PDC split into to two paired and entangled photons, we know only one photon ever passes each of the intersection areas at a time, therefore the entanglement behavior for photons between A & B should be the same regardless of where on the rings of light they may be found. Although to match the entanglement results we find between the traditional Alice & Bob test areas the detections we find a A1 and A1 must be combined as if from one detector to duplicate the photons measured coming from the singe Alice test area. Likewise, B1 & B2 results must be combined.

    Now with the test areas individually producing photons of known polarization we can use classical Malus' Law to predict the number of photons to pass polarization tests of various angles and statistical combine them between two sides to produce a LR prediction for Correlations. For example when 50% of the photons should pass on the A side and 50% are predicted on the B side they would be a 25% probability that the two would be passing at the same time to allow a correlated detection. By carefully following Malus' Law and apply classical statistics to predict correlations for a full range of possible test angles averaged together, it should be clear that the 25% to 75% correlation plot is the only possible result a Local Realist can expect. Only be applying something other than Classical statistics and Malus Law could any other result be predicted, and I am not aware of any other classical rule that can be used here.

    What’s more this experiment is relatively simple and can be physically performed. But to ensure that only classical physics is in the testing any possibility of QM entanglement needs to be removed. Here again the separation of test areas into four physical locations allows us to do just that. Areas A1 and B2 shown in the diagram can be filtered through a Vertical polarization filter and a horizontal filter can be placed in front the A2 and B1 test areas ahead of normal correlation testing. Since photon polarization is known and matches those filters we know 100% of the photons should pass with no change to our classical predictions. But the filter will confirm the polarization each photon by a measurement as it passes; therefore destroying any possible entanglements according to the rules of QM. Thus no possible entanglements interfere with what will be a classical test of correlations based on known classical variables (i.e. Maules Law). I am positive such a test will confirm the classically predicted LR 25% to 75% correlation exactly.

    Naturally a second version of the experiment can be run with the fixed polarization filters removed to allow any unknown effects such as ‘entanglement’ through. In this second experiment, the collective A1+A2 to B1+B2 correlations will perfectly match the traditional entanglement test matching the QM correlation prediction.
    If anyone believes some other results should be found for either of these experiments, I’d love to see a different prediction documented. Although I don’t see how any other would be convincing without the experiment actually being preformed to prove the case. I have no doubt my predictions will be confirmed by experiment. I’ve tried, but have been unable to find where any test like I’ve proposed here has ever be done or even suggested before.

    Although a simple point, and I’d like to find where some Lab somewhere would see the value in making the point clear with real experiment verification. It seems simple enough experiment that any competent Quantum Optical Lab anywhere to perform.
    I also believe even as a though experiment, even before a real experiment is performed, this has a significant impact on how the Bell Theorem has been applied in the past. Directly impacting the Einstein Bohr debate on QM completeness and whether or not the idea of a Hidden Variable.

    ©2007 Randall B

    Attached Files:

    • PDC4.jpg
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  4. Aug 18, 2007 #3
    The Flaw in applying Bell’s Theorem

    The significance in actually performing the experiment that defines Local Realists with real results comes from careful consideration of the results when the filters blocking “entanglement” are removed allowing the QM predictions to be correctly revealed by the experiment. Clearly the 25% to 75% correlation as shown in the diagram in the OP is the correct LR prediction and result based on known classical science about how light behaves (Mauls Law). And in that correlation graph by measuring from the center 50% probability line we see the prediction by QM plots a line twice as far from 50% as predicted by the LR. This produces a plot from 0 to 100% that goes above and below the Bell Inequities defined by the Bell Theorem. Something new and weird not defined by classical science. at least not currently, must be happening with those filters removed. The question is could that something be a classical but unknown hidden variable or must it be something unknowable in physical terms only definable as “entanglement” or “superposition between two photons”. If not that at least something unrealistic to our common understanding like extra dimensions possibly even carrying invisible guide waves.

    Our current scientific logic assumes some non-local entanglement solution must be correct because we think no Local Hidden Variable is possible. But, I believe Alain Aspect along with theorists and experimentalists before and after him have miss-applied the Bell Theorem to the observed results. They have always applied Bell Logic to a SINGLE variable. But there is no reason to think that the classical LR predictions defined as a “Known Variable” are not a part of our solution. Certainly such a “Known Variable” that existed before the filters are removed from A1, B2, A2, B2; is still there when the full 0-100% plot is achieved without the filters. That is adding something in addition to that “Known Variable” is being added by removing those filters and that addition does not need to account for the full plot line as predicted by QM. It only needs to move the line already established by the LR “Known Variable” out to that line.

    Meaning we must have TWO Variables involved! And the second unexplained variable would only need to increase the LR result from 75% up to 100% on one end and reduce it from 25% down to 0% on the other. In fact the “probability range” of an independent “Hidden Variable” would be identical to the Known LR Variable previously defined. (Although it would need to apply itself adding against the Known LR Variable in a perfect way to match the correct Observed results). The point is such a HV would not violate Bell Inequities. For the last several decades the Bell rules have been applied assuming only one variable could be used to solve the problem. Bell himself incorrectly IMO assumed an interrelated “set of variables” could be treated as a single variable. However there is no Scientific Logic that prevents Two Independent Variables, each well within Bell Inequities, from working together to exceed those Bell Inequities. (If anyone does know of a rational line logic that claims two independent variables can be treated as a single variable - that would be worthy of discussing)

    Rather than proving a Local Hidden Variable as impossible, the Bell Theorem instead defines parameters within which a Local HV must fit. The challenge is finding a logical place within Classical Science to define a Hidden Variable. A scary thing to consider for modern scientists. Vindicating the Einstein claim of a Local and Realistic reality would mean ideas like QM BM MWI Strings can be complete correct in their foundation. All those 20th century ideas are in part Non-Local and/or Un-Realistic. Granted if we can not find such a solution we may wish to continue considering any of those ideas – but we must also admit no body really looked. At least until now.

    Before I post my version of a well diagramed image of the Hidden Variable I wish to give all those on this forum that have worked so hard at considering this issue from both sides (Local vs. Non-Local) one last chance to find the HV on their own. Especially, DrChinese who has been a bit inactive on the Forum lately due to a very busy Summer. But I suspect he will easily recognize the significance of define a legit HV. Personally I think DrC has the best shot at successfully defining the HV. He has always seemed the most rigorous a logical in dealing with this often contentious subject, I believe the clues and information here will make the difference. I wish to give DrC and others deserve at least one weekend to try to do it on there own before I post my solution including a Copyrighted Published Reference.
    And of course this solution will not be based any mysterious math formulas like unrealistic invisible BM guide-wave formulas. Instead I am talking about a drawing of something clearly local & realistic that based on the drawing alone will successfully solve entanglement and even the sunglasses HDV paradox. Both in irrefutable local terms with no Weird Action at a distance required.

    DrChinese, let me know that you’ve seen this by posting here and advise if you feel this weekend is enough time to consider the issue. I’m rooting for you, but I don’t want you to lose too much sleep pondering it over to many late evening – I’ve done that already.

    ©2007 Randall B
  5. Aug 21, 2007 #4
    Last Hint To Finding Einstein’s HV

    Before revealing the HV solution, I though I’d give one last hint for those wishing to discover a solution on their own. Although a HV solution capable of solving the Bell Polarization Entanglement Issue of PDC experiments, may not be expected to directly solve other paradoxes such as interference fringes with double slits. We should expect it to explain a polarization paradox like the diagonal sunglasses issue. So, it is worth reviewing and considering that problem while attempting to devise a HV solution in “Local” terms.

    In Classical terms based on INTENSITY the Multiple Polarization Filter Problem is describe and explained using Malus' Law for light passing through Two & Three Polarization Filters arranged HV or HDV giving two diagrams:

    Code (Text):
    Light >> [B]–H–[/B] Light(1/2) >> [B]|V|[/B] Zero Light >>

    Light >> [B]–H–[/B] Light(1/2) >> [B]/D/[/B] Light(1/2)(1/2) >> [B]|V|[/B] Light(1/4)(1/2) >>
    This change in Intensity for light is in the classical formula :

    {\mathbf{A}} = B\cos (kz - \omega t){\mathbf{x}} \pm C\sin (kz - \omega t){\mathbf{y}}

    However, the 20th century (after Plank & Einstein) was soon able to dim the light to test this phenomena literally one photon at a time. Using a “*” as a Photon displayed below, with tests in large multiples of 8 “*” photons presented to the filters one at a time gave test results that averaged as follows in two diagrams:

    Code (Text):
    * * * * * * * * >> [B]–H–[/B] * * * * >> [B]|V|[/B] Zero photons >>

    * * * * * * * * >> [B]–H–[/B] * * * * >> [B]/D/[/B] * * >> [B]|V|[/B] * >>
    The significance here is that as 4 Horz. Photons pass a Diagonal Filter they do not have their intensity reduced by 50% as called for by the Classical formula above. There is no such thing as a individual photon of ½ intensity. Rather only two of four photon are seen as passing and the same elimination of half the photons by the V filter for the Diagonally Polarized stream of Photons. The reduction of intensity Classical Solution cannot be applied or be correct. Giving us an unresolved paradox until the Math of QM was applied that looks something like :
    a^\mu (x) = (2\pi )^{ - 3/2} \int {\frac{{d^3 p}}
    {{\sqrt {2p^0 } }}} \sum\limits_\sigma {\left[ {e^{ip \cdot x} e^\mu ({\mathbf{p}},\sigma )a({\mathbf{p}},\sigma ) + e^{ - p \cdot x} e^{\mu *} ({\mathbf{p}},\sigma )a^\dag ({\mathbf{p}},\sigma )} \right]}

    Not that I can do this form of math myself, but it essentially contains a probability function randomly applied to each individual photon as it passes each polarization filter. That random probability happening only at a future filter interaction was of course the problem Einstein had with the QM formulation; insisting instead that a classical ‘unknown’ and ‘hidden’ variable transmitted with each photon from one filter forward to the next filter must be in play. Although, this is only a little less complex than our entanglement issue, it should help provide clues to a Classical “HV” that must be able to solve both these polarization paradoxes in classical understanding. This “Sunglasses problem allows us to more clearly describe the terms ‘unknown’ and ‘hidden’ as we search for a description of the HV.

    Unknown: meaning that prior to successfully going through the first filter no matter how well defined a photon is we the value what the HV will be after passing may not be predictable.
    Hidden: after passing the second filter polarization will be realigned and no additional tests can be preformed to detect what the value of the HV might have been.
    And of course there is no known way to make non interfering measurement while the photos are in route between two filters.

    Logically theories like OQM, BM, MWI, Strings, can no longer claim a HV is not possible. With the possibility of Two Variables as described in the previous post the those “Non-Local” theories can no longer look to Bell Theorem to provide a convincing “Negative” proof against HV’s and a “local reality”. Nor does that possibility justify simply declaring HV’s must exist because like Einstein we might feel in our gut that should. For a Local and Realistic HV to be a convincing possibility it must still be described in detailed classical terms to be convincing, such as in a drawing to give it tangible form in a classical sense.

    I’ll allow another night or two for DrC and others on this forum to consider a solution on their own before posting my solution for analysis by all on PF. Also FYI, as I am sure most of us here visit and use other Scientific Forums, this will be the only group I will be give these hints to allow someone a shot on their own to complete a solution. I don’t know of any other forum that has a chance of considering such a controversial topic on a strictly scientific and logical basis without resorting to dogmatic opinions from various theories.

    ©2007 Randall B
  6. Aug 22, 2007 #5


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  7. Aug 25, 2007 #6
    I agree that QM is by definition “Non-Local” in every sense. And that the “unrealistic” attempts of Theories like BM that attempt to recover a sense of “Local” with “unrealistic” guide-waves is still Non-Local in the Einstein meaning of local where “realistic” must be included as well (as explained in the link you provide). Realistic meaning “classically real” without some invisible dimension carrying a guide-wave. If BM someday did prove such invisible dimension as real, BM would still be “unrealistic” in the classical sense – reality would be not be classically realistic. Bell cannot help with this issue, just as it cannot help decided between oQM vs BM or any other Non-Local. Bell can only judge the viability of a Local & Realistic HV as Einstein expected.

    It is on this point, the Bell testing HV viability, where is see a problem and it shows in Hrvoje Nikoli´ comments where he says :

    The problem I see with it being “clearly nonlocal” is if P(x, y) comes from a P(x) correlation with P( y) where P(x)= P(xK+xU) made up of two variables, “Known” & “Unknown” and likewise for P(y). Now that classical probability distribution looks like P(xK+xU, yK+yU) dependent on four separate variables. If these four coordinate properly there is no reason the net result cannot exceed the Bell inequities to match observations as required, while the individual variables remain realistically within the Bell inequity limits.
    This would mean Bell is no longer able to falsify the idea of a HV.
    That is my point in post #2 & #3; that a HV could be viable as a local solution – since QM cannot be “Einstein Local” it therefore could be wrong, or as Einstein put it “incomplete”. And for Neils Bohr and Copenhagen “incomplete” and wrong is the same thing for QM.

    This corrected view of Bell showing that a HV is possible is not proof that Non-Local theories are wrong. The Bell Theorem is solely a test of viability for the hidden variable no more than that. What this new conclusion from Bell does is justify renewing a legitimate search for a classical description of a HV clearly stated in local and realist terms. Assuming more than that without a defined HV is only arguing opinions without substance, which is why a well understandable description of a local HV is so important.

    Randall B
  8. Aug 25, 2007 #7
    THE Hidden Variable

    Attached is an image that tangibly describes a pair of photons produced from paramedic down conversion, based on a classical hidden variable defining individual photon polarization. It is extracted from a new book “Proving QM Wrong” © July 2007 pub. by AuthorHouse. References to the diagram & idea should be to that book where all rights are reserved. The book suggests nothing in the way of a new theory; it instead applies the scientific method in a commonsense logical approach to build on the Local Realist case of Einstein. IMO it was more important to establish a Hidden Variable as real with falsifiable experiments before defining a new theory based on it. Including any details of a new theory are too easily declared ‘crackpot’ when the main point and objective of the book needed to be defining doable experiments with Hidden Variable predictions that can verify or falsify a classical description of the HV.

    The ability to define the polarization of an individual photon in a two dimensional diagram is clearly a local and classically realistic description. The current definition of individual photon polarization based on probabilities is replaced. As the diagram shows, a fixed area of detectable polarization is defined in black for each individual photon as being 90° wide. Each photon in a beam of polarized light has the center of this detectable area within 45° of the beam’s polarization. For vertical light, each photon would be detectable on the vertical axis, but never extend the detectable area across the horizontal axis. This applies to all photons randomly distributed alignments on either side of vertical, only requiring the center point be within a 45° limit. We can easily see that exactly half would be detectable by a future left side diagonal polarization test, and the other half would always be detectable by a right side diagonal polarization test. With this description is easy to solve the paradox of the diagonal filter placed between horizontal and vertical filters allowing light to pass. Each photon has a fixed polarization established when they exit a filter that defines locally in advance which future diagonal filter they will pass. As each photon successfully passes a new filter, its fixed polarization would be randomly realigned to within 45° of the new polarization alignment for the total new beam of light. Notice how this individual photon “width” of fixed polarization remains “Hidden” as only one test on the photon can be made. Each “test” or filter destroys the prior photon polarization and randomly establishes a new alignment within the limits of that local filter.

    In the case of paramedic down conversion, the diagram shows how PDC type II photon pairs with the exception of a 90° rotation can have identical fixed polarization configurations. Notice how the four points that indicate the detection transition points for both of the paired photons is exactly the same. This means each photon is carrying with it by means of defining itself enough information about the twin to predict how the twin will behave without sharing any additional information. No FTL, no entanglement wave function collapse, no information from a distance is required. All the needed information is inherently a part of each photon based on how it was defined during the local creation of the photon pairs.

    On paper this demonstrates using this new purely Local Definition of photon polarization as the Hidden Variable (previously Unknown part) in combination with how it builds Polarized Light (the Known un-hidden part) is capable of resolving the EPR Bell polarization paradox in local terms. For myself, I do not see how this description can fail to solve the EPR paradox in local terms. I believe the EPR Bell experts on this forum, like Dr. Chinese, that apply this definition of a HV to there own thought experiments will come to the same conclusion. I’d be very interested to hear from them what they find in using this HV and if any flaw can be found on paper.

    To be completely convincing all that remains is designing and running experiments that can positively confirm this HV definition as correct. Naturally the first one experiment would be re-doing the EPR “entanglement” tests that had used two test areas of mixed polarizations with one using four test areas of known polarizations as outlined in the post #2 diagram.

    ©2007 Randall B

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  9. Aug 25, 2007 #8
    Sory, but your article begins with a false statement:

    A strictly deterministic theory (superdeterministic in Bell's words), like Bohmian mechanics, is imune to those "no-hidden-variable theorems".

    Therefore, unless you can extend Bell's theorem to this type of theory, you cannot prove non-locality.

    The question is, is it possible, even in principle, to distinguish between a genuine non-local mechanism and a local one that uses some type of synchronization for producing apparently non-local effects? I think that, in a strictly deterministic universe, the answer is no.
    Last edited: Aug 25, 2007
  10. Aug 25, 2007 #9


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    That is certainly false. There are obviously senses in which QM is local. For example in the sense that under unitary evolution, the variables in a region of space-time have no influence on any variables that lie outside of that region's future & past lightcones.
  11. Aug 25, 2007 #10


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    How do you figure? Every deterministic theory is a probabilistic theory, albeit with a boring probability distrribution. And even in a deterministic theory, one can still use probability to describe, for example, hidden information.
    Last edited: Aug 25, 2007
  12. Aug 26, 2007 #11
    Bell's theorem requires the assumption that the measurements' angles are statistically independent (free) parameters. In a complete deterministic theory this assumption might fail.
    For example, one can propose that the spin of the entangled particles, as they are produced by the source, is "chosen" as a result of an incomming signal from the detectors, containing information about the detectors' state. In such a case, the detectors' orientation is not a free parameter anymore, and Bell's theorem does not apply.

    Even Bohmian mechanics can be made, formally, a local theory by describing each particle's trajectory only as a function of the initial conditions at the big-bang.
    Last edited: Aug 26, 2007
  13. Aug 26, 2007 #12
    The BM theory has always been acceptable as a possible valid theory by Bell, but no more likely than QM, MWI or any other nonlocal since the only thing Bell Theorem can evaluate is a strictly local HV as Einstein expected.
    The problem with Bohm and Bohmian Mechanics. is that “BM Local” is not the same as "Bell Local" (Einstein Local) because "some type of synchronization" using guidewaves and/or a deterministic history is not strictly local. The Bell theorem has never rejected BM because BM is not a Bell Local Theory, just like QM is not Bell Local.
    For example Bohmian Mechanics cannot produce a drawing of a photon that can display the guidewave or past history information as part of the photon. No better than QM make a drawing that includes the HUP in a drawing of an individual photon. Both these theories are nonlocal in the “strictly local” manor that Einstein expected, which would expect a tangible drawing of a “strictly local” description to be possible.

    The real question here is, has the Bell theorem incorrectly rejected the possibility of a “strictly local" description from including enough information to solve "entanglement" without nonlocal ideas like BM or QM. I believe it has Bell has been misunderstood and can be demonstrated by the amount of information included on the drawing of two correlated photons in post #7. Let's first dissect the information we can shown in detail about the vertical photon in that drawing. Using a 360° compass headings receive this vertical photon has a polarization axis marked by the dart about 30° clockwise from 0° straight up vertical. Although not in perfect alignment with vertical, it is still detectable by a vertical polarization test. Or any polarization test within 45° of the 30°/210° polar axis of this photon. The measurable element of the photon is not its polar axis, but the transition points from detectable to non-detectable. For this photon, those four points are [75°, 165°, 255°, 345°] which give a complete description of this photon’s vertical polarization.

    Now lets look at the minimum required information to describe the horizontal photon, produced when PDC created the vertical photon. This horizontal photon has a polarization axis marked by a dart about 30° clockwise from 270° flat left at 300°. Again we can define a complete description of this photon’s detectable polarization area by the transition points from detectable to non-detectable. These are 45° either side of the 120°/300° polar axis puzzle of this individual photon giving [75°, 165°, 255°, 345°]. Now can this information about the horizontal photon somehow be carried by the vertical photon? Of course it can, it's these are exact same transition points that described the vertical photon. No additional information is required, no past history, no guidewave information, no HUP uncertainties need be applied. Only “strictly local” info already a part of the photon is needed, just as Einstein expected, even as the complete “fixed width” of an individual photon remains “hidden” from direct measurement. This “strictly local” information (not BM local) should be all that is needed to solve the EPR polarization paradox with Bell Local information.

    I am convinced that no on paper analysis of a thought experiment will reveal a flaw in this Local Hidden Variable’s ability to solve EPR-Bell. I’m also convinced simple laboratory experiments can confirm that this local solution is at least viable. And additional and repeated experiments have the real potential of becoming accepted as “Proving Quantum Mechanics Wrong”. Just as convincingly as Einstein is currently considered to have been wrong to say “God does not throw dice”. Rather than repeating old tests, we need new tests that can show if this is so or not.

    Randall B
    Last edited: Aug 26, 2007
  14. Aug 26, 2007 #13


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    If a theory violates the no-conspiracy assumption, then Bell's theorem does not apply. This has aboslutely nothing to do with whether or not the theory is deterministic.
  15. Aug 26, 2007 #14
    First, I think there is nothing "conspiratorial" in the assumption that the emission can be conditioned by the absorbtion (detection). In fact, there is a QM interpretation, the transactional interpretation that postulates something along this line. Of course, Cramer's TI is non-local, but locality can be reintroduced with a subsequent assumption, that the entangled particles can extrapolate the detectors' state at the moment of detection from the information available at emission. This extrapolation is only possible in a deterministic theory, where knowledge of the past state uniquely determines the future state.
    If a theory is non-deterministic, the only way EPR correlations could appear is by the way of an instantaneous information transfer.
    In other words, If the choices of Alice and Bob are dictated by an pseudorandom deterministic mechanism, EPR correlations may be caused by an event in their common past. If the choices are truly random, non-locality is the only explanation.
  16. Aug 26, 2007 #15


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    Sure, but the reason we make the assumption is to rule out conspiracies; I presume that's why it's so named.

    Why would you think unique determination is a necessary condition?
  17. Aug 26, 2007 #16
    Bohmian Mechanics and “BM Local” require some level of “conspiracy” and/or extracting future information from initial conditions of test particles and measuring devices. This is well outside of the idea of “Local” in any sense that is important to EPR & Bell correlation tests. At best, “BM Local” is an indistinguishable analogy to QM uncertainty, and interchangeable with it as Non-Local when compared to the strictly local meaning intended in Bell Local and Einstein Local.

    You have probably gone through a detailed angle-by-angle analysis of the EPR Bell polarization experiment to see how well BM approach does work in successfully resolving it, that's good. I have done the same for the completely and strictly local Hidden Variable I provide and described in Post #7 & #12 but I just one person. The propose of this thread is to ask you and others to put your experience into evaluating either on paper or by thought experiment the viability of this local HV as drawn in the Post #7 diagram, not a debate about BM.
    Are you willing to do that?
    I have yet to see any problem with this new local HV solution and I wonder if you recognize the significance if it is shown to be true.
    Have you even considered what this could mean to both QM and BM?
    If experimental evidence comes in showing that such a simple and local HV solution is valid, then Occum’s Razor would expect this simple solution to be superior to both BM and QM. Both require weird actions and behaviors explained by overly complex mechanisms when compared to a simple HV that is Bell & Einstein local. The question is does it look like this HV version of a photon description look like it can really work to resolve ‘entanglement’ locally? Meaning the prior Bell Theorem conclusions about a Einstein local hidden variable was wrong, and current theories may need significant rethinking.

    This is much more significant than grousing over how BM can be recognized as local or non-local,
    So if you intent is only to highjack a thread with promoting the BM interpretation please take it somewhere else, BM is fifty years old a frankly has not been that successful.
    Otherwise please address this new description of an Einstein Local Hidden Variable directly. It is at least a new idea.

    As requested in the OP this is not a thread to open up a side skirmish about determination or determinism please take how BM relates to that philosophy to another thread.
  18. Aug 26, 2007 #17
    Just to make a small side note; as I remember you are in favor of the Everett interpretation, right ? Well, then you undoubtedly know that in that interpretation, Bell's theorem becomes irrelevant (because no objective reality is attached to *both* measurements as they occur). Actually, it is pretty easy to construct local realist models in the Everretian spirit (providing for the exact singlet correlations); I seem to remember that Adrian Kent has done something like that.
    Last edited: Aug 26, 2007
  19. Aug 26, 2007 #18
    Why are you citing items from a self-publishing company? (Sounds kind of "crackpot", no?) Hasn't any of this been peer reviewed?

    The purpose of this thread is for us (self-declared experts! :wink:) to evaluate the viability of your local HV theory?

    Are you asking us to explain a problem with this theory (kind of like debunking a specific perpetual motion machine)? Or, as per my impression, were you actually advocating this non-peer-reviewed theory over mainstream theory (which would be a fundamentally different enterprise)?

    At first one feels bad taking action that can be perceived as outright "censoring new ideas". But there is a place for new theories, and that is firstly the expert peer reviewed journals. How can the public be taught technical subjects if pop. sources present well verified knowledge alongside wild unsupported claims?

    In that vein, would I be mistaken to describe the topic of this thread as being a "new or non-mainstream theory or idea that has not been published in professional peer-reviewed journals or is not part of current professional mainstream scientific discussion"?
    Last edited: Aug 27, 2007
  20. Aug 27, 2007 #19


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    If I understood you correctly, you claim that Bohmian mechanics is actually local? I strongly disagree.

    Note, on addition, that Bell was inspired by Bohmian mechanics when he discovered his famous theorem on the relation between QM and local hidden variables.
    Last edited: Aug 27, 2007
  21. Aug 27, 2007 #20
    First, I apologize for not responding to earlier this post. I simply missed it.
    I don't see how this LHV theory explains EPR, in fact I am pretty sure that it fails. Did you try to make some calculations, taking different photon orientations to see if QM prediction is recovered? In other words for the case when the detectors' orientation are changed randomly between 3 measurements axes do you get the same result for about half of the time?

    BM can produce a drawing as you sugges if the universal wavefunction (which is stationary) and the particle configuration at the big-bang (a constant) is included in the photon's law of motion. Ugly, indeed, but possible.
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