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New Quantum Interpretation Poll

  1. Jan 7, 2013 #1
    A Snapshot of Foundational Attitudes Toward Quantum Mechanics
    http://lanl.arxiv.org/pdf/1301.1069.pdf
     
    Last edited: Jan 7, 2013
  2. jcsd
  3. Jan 8, 2013 #2

    DrChinese

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    Cool paper! There were 33 respondents, and these included some of the top names in the field.

    A few additional comments from the paper:

    -Interpretations themselves: 42% identified with Copenhagen, 18% with MWI, 0% with Bohmian, and the remainder split amongst various non-specific (such as "information based").

    -They conclude: "Yet, nearly 90 years after the theory's development, there is still no consensus in the scientifi c community regarding the interpretation of the theory's foundational building blocks. Our poll is an urgent reminder of this peculiar situation."
     
  4. Jan 8, 2013 #3
    I'm not sure but I feel left out, for some reason. :frown:
     
  5. Jan 8, 2013 #4

    DrChinese

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    Gosh, I have no idea why. :smile:

    It is interesting that even though there were no Bohmians, 12% saw action-at-a-distance in Bell tests. And 36% had some notion of non-locality (although that could mean almost anything).
     
  6. Jan 8, 2013 #5

    George Jones

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    Yes!
    I would like to know the ages of the respondents, and the age distributions for the responses to the questions.
     
  7. Jan 8, 2013 #6

    stevendaryl

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    Is Copenhagen actually an interpretation? It seems to me an attempt, one that's mostly successful, to get on with using quantum mechanics without waiting for agreement about what it all means.
     
  8. Jan 8, 2013 #7

    Nugatory

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    From a historical perspective, it seems fair to consider Copenhagen an interpretation (the first one?). That doesn't necessarily conflict with your equally fair description of it.
     
  9. Jan 8, 2013 #8
    I believe the pilot-wave interpretation predated the Copenhagen interpretation. It just wasn't as well received.
     
  10. Jan 8, 2013 #9
    12% means 4 people according to the paper, maybe that could be the 3 mathematicians and 1 philosopher....! :tongue2:
     
  11. Jan 8, 2013 #10

    atyy

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    The poll only included many-worlds worlds in which the respondents were not Bohmian. In other worlds, there were definitely Bohmians;)
     
  12. Jan 8, 2013 #11

    DrChinese

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    I would be cautious on this point, there may be a slight bit of revisionism going on with this particular idea (not on your part, from the recent historical paper I am fairly sure you are familiar with). There are some rabid dBB folk out there who are trying very hard to twist historical opinion around in some very odd ways. You can see it in Wiki and several other prominent spots, and their views are quite at variance with the mainstream. The basic idea is that Bohmian mechanics should be considered as the "standard" or first interpretation and that Bohr and others squeezed out that viewpoint in favor of Copenhagen. That is far fetched, seriously.

    Much of the school of thought known as Copenhagen really came out of the same conference where de Broglie presented his early ideas on the matter. Obviously, people were trying to get their heads around the new ideas being presented. And as has been pointed out by many, Copenhagen can really mean a lot of different things anyway. I think of it as a minimalist interpretation where the formalism rules, not as an expression (for example) of Bohr's viewpoint.
     
  13. Jan 8, 2013 #12

    DrChinese

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    They were all Bohmian in some branches. :smile:
     
  14. Jan 8, 2013 #13

    atyy

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    Technically, people like Valentini, although definitely Bohmian, are not in favour of the Bohmian "interpretation", since the consideration of non-equilibrium presumably allows deviations from quantum mechanics, ie it is a different theory and not just an interpretation. Do the questions allow for this possibility?
     
    Last edited: Jan 8, 2013
  15. Jan 8, 2013 #14

    kith

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    Yes. Nobody chose the answer "There is a hidden determinism" to the question "What is your opinion about the randomness of individual quantum events?"

    It is quite interesting that not a single one of these foundations researches takes the possibility of (deterministic) hidden variables seriously.
     
  16. Jan 8, 2013 #15

    atyy

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    Interesting indeed. However, since no names were attached to the votes, we don't know who voted for what. So how do we know they took the poll seriously?
     
  17. Jan 8, 2013 #16

    kith

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    We don't know for sure but I personally think the people answered honestly. Why should they spoil Schlosshauer's and Zeilinger's poll instead of just not taking part if they are not interested in contributing?

    The fair sampling loophole seems more important to me. ;-)
     
  18. Jan 8, 2013 #17

    atyy

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    :rofl:
     
  19. Jan 9, 2013 #18

    Demystifier

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    Agree!
    For example, at page 8 they say:
    "Similarly, the fact that de Broglie–Bohm interpretation did not receive any votes may simply be an artifact of the particular set of participants we polled."

    For comparison, in another recent unfair sampling of leading quantum foundationalists:
    M. Schlosshauer, Elegance and Enigma - The Quantum Interviews (2011)
    3 of 17 (i.e., 18%) people prefer de Broglie–Bohm interpretation.
     
    Last edited: Jan 9, 2013
  20. Jan 9, 2013 #19

    vanhees71

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    Well, this seems to be a somewhat strange poll. Because they have asked "experts" on "interpretation", which tend to have sometimes strange views on this issue (don't take me too literally, I'm also interested in these issues and find it important). That nobody votes for the "Minimal Statistical Interpretation" or "Ensemble Interpretation" (which I think is pretty much the same, although you can never be sure ;-)). Also to vote for "Copenhagen interpretation" is a very uncertain issue, because there are as many "Copenhagen interpretations" as there are people claiming to follow this interpretation. It's a pretty unsharp notion (thanks to Bohr and Heisenberg who were a bit too "philosophical" and not enough "mathematical" to my taste), what you call "Copenhagen interpretation". I think it's pretty problematic.

    I'm clearly a follower of the "Minimal Statistical Interpretation", and with this there is no trouble and this also is the way, how quantum theory is applied to real-world applications since measurements are always done on an ensemble of many equally but statistically independently prepared "quantum systems". I don't know of any example for an experiment, where there is a contradiction to empirical evidence. Concerning "locality" one has to clearly distinguish "local interactions", which so far seem to be realized in nature, because there is no contradiction to the standard model of elementary particle physics, and this is a local relativistic QFT, and "non-local correlations" as described by "entanglement", which are well established by real experiments now, which clearly are in favor of the violation of the Bell inequality (and similar inequalities) and with the predictions of quantum theory (in its minimal interpretation).

    I don't see any need for additional elements of interpretation, be it "many worlds" (adding unobservable parallel universes to the interpretation, a collapse of the quantum state (as proposed by the Copenhagen-type interpretations), or unobservable "trajectories" a la de Broglie/Bohm (which attempts to introduce a kind of "nonlocal realism", whatever the precise meaning of this notion might be), solipsism (only a recognition of a measurement result by a "conscious observer" determines the quantum state in terms of a Collapse, which is a pretty strong flavor of the Copenhagen type, usually known as the "Princeton Interpretation"). All the observable facts are identical in all those interpretations, and the "down-to-earth-no-esoterics" minimal statistical interpretation has no problems, although some people think that there is a problem, because this admits that one cannot make predictions about the behavior of a single system, which of course is true, but as I said above, when you have a probabilistic theory, you have to use an ensemble to prove its predictions. As long as there is no deterministic theory which is as successful as quantum theory, I think we have to live with this "incompleteness of quantum theory". Whether or not nature is intrinsically and irreducibly probabilistic and inderterministic is of course another question, which can only be decided when one has such a deterministic theory, which then should be non-local due to the issue with the Bell inequality, and so far nobody has been able to find such a theory which is as comprehensive and successful as quantum theory.
     
  21. Jan 9, 2013 #20
    All the observable facts with respect to how quantum mechanics is currently formulated. In principle, a clever person might be able to find ways in which the various interpretations would distinguish themselves in predictions for proposed, testable extensions to the postulates of quantum mechanics. That is exactly what people who work on quantum foundations spend a great deal time trying to think of. Taking the position that there's no point distinguishing between different models that we haven't yet figured out how to experimentally distinguish is functionally useless.
     
  22. Jan 9, 2013 #21
  23. Jan 9, 2013 #22
    I had to read that twice before it "clicked" :biggrin:
     
  24. Jan 9, 2013 #23

    stevendaryl

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    I don't see that Many Worlds amounts to injection "additional elements" to quantum theory. If electrons and atoms and molecules can be in superpositions of states, then there is no reason, a priori, that people and solar systems and universes can't be in superpositions of states. To me it seems that it's not Many Worlds that requires something additional, but the other way around, you need something additional to allow for microscopic superpositions and disallow macroscopic superpositions.
     
  25. Jan 9, 2013 #24

    stevendaryl

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    That seems wrong to me. The whole point of EPR is that in certain situations you CAN make predictions about the behavior of a single system. If you produce a twin-pair with total spin 0, and one experimenter measures spin-up for one of the particles along some axis, then you know with certainty that another experimenter is not going to measure spin-down for the other particle. If a hydrogen atom is excited and later emits a photon, quantum mechanics allows us to predict with near-certainty what the possibilities for the energy will be.

    I think that it's absolutely not correct for people to say (I'm not sure if you're saying this, or not) that people have trouble with quantum mechanics because they can't accept intrinsic uncertainty in nature. That's not true at all. There is no conceptual difficulty with allowing for nondeterministic dynamics. You can imagine that particles are equipped with a kind of random-number generator, and what they do depends not only on their current position, momentum, etc, but also on the value of the internal random number. That might be annoying to people like Einstein who believe that "God does not play dice", but there is no conceptual difficulty with it. But the point of EPR is that quantum mechanics ISN'T like that. It doesn't work like an ordinary stochastic theory, precisely because of the ways in which makes some DEFINITE predictions. It's the nonlocal correlations that make QM strange, not the probabilistic aspects, and I don't see how an "ensemble interpretation" helps to understand those nonlocal correlations.
     
  26. Jan 9, 2013 #25

    kith

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    Maybe supporters of the Ensemble Interpretation think that there are no foundational problems and don't attend such conferences. ;-)

    If you have a real ensemble in your experiment -i.e. a gas of atoms-, this is straightforward. But if you prepare one system at a time and repeat your experiment over and over again, it seems a bit odd to me to say that the only physical reality lies in the abstract ensemble.

    However, this view is quite similar to the spirit of Copenhagen. Both agree that the physical properties of a single system described by a superposition are not well-defined. The only difference is that the copenhagenist would say that in an ensemble of systems in an eigenstate, the corresponding physical property is a property of every single system.
     
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