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  1. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    18 Dec '14 08:21
    Hey, what's all this about? I stumbled across it by accident, but it appears to be a rather drastic reinterpretation of quantum theory. In fact it is a deterministic theory. I'm not surprised that deterministic theories are still being entertained, but this seems like a respectable effort.

    http://en.wikipedia.org/wiki/De_Broglie–Bohm_theory

    http://www.bohmian-mechanics.net
  2. 18 Dec '14 14:55
    Bohmian mechanics is the most well-known attempt at a deterministic quantum theory. However, it is not that popular because, as far as I know, it doesn't do any additional empirically verifiable predictions compared to the orthodox interpretations.
  3. 18 Dec '14 16:24 / 18 edits
    Originally posted by Soothfast
    Hey, what's all this about? I stumbled across it by accident, but it appears to be a rather drastic reinterpretation of quantum theory. In fact it is a deterministic theory. I'm not surprised that deterministic theories are still being entertained, but this seems like a respectable effort.

    http://en.wikipedia.org/wiki/De_Broglie–Bohm_theory

    http://www.bohmian-mechanics.net
    The conventional interpretation of quantum physics which is called the "Copenhagen interpretation", which, like many scientists including Einstein I should add, I think is erroneous. This is because it leads to such philosophical problems such as what is called the "measurement problem". Basically I and, even in the modern day, many scientists (although many more do not), actually reject the Copenhagen interpretation in favour of what is called the "realist interpretation" of quantum physics.

    I cannot help but have the suspicion that the Copenhagen interpretation has only become the most popular one because both many scientists and the public alike liked the weirdness of its implications rather than because of any real sound rational scientific reason although I can also see how the Copenhagen interpretation could come from a naive application of Occam's razor which, although a perfectly valid principle, should be used with some caution.

    It is an extremely common modern day misconception that quantum mechanics says quantum events are not determined but actually quantum mechanics doesn't specify whether quantum events are determined or not and the Copenhagen interpretation isn't the actual quantum mechanics but is rather purely a metaphysical interpretation of quantum mechanics thus quantum mechanics doesn't specifically say/imply a realist interpretation must be wrong nor merely improbable.

    The "pilot-wave theory" (in your link ) , is just one example of such a realists interpretations out of several workable realist interpretations and it happens to be the one that Einstein, rightly or wrongly, thought correct.

    Although I am a "realist" meaning that I think a correct interpretation of quantum mechanics must be a realist interpretation, I personally remain uncommitted to any specific realist interpretation until if or when I know of evidence to support one over the others.

    One thing that should be noted is that there couldn't ever be evidence for the Copenhagen interpretation over all possible realist interpretations because one of the characteristics of the Copenhagen interpretation is that it cannot ever be proven true even if it is true although it might be falsifiable if a realist interpretation could ever be so constructed to make a prediction that the Copenhagen interpretation doesn't make and which would be possible to prove and then empirical evidence proves it.
    But what all that would mean is that, hypothetically, if the Copenhagen interpretation is the true one in reality, the debate of which interpretation is the true one will never ever go away for as long as thinking people exist who know of such interpretations.
  4. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    18 Dec '14 18:48 / 1 edit
    Originally posted by humy
    The conventional interpretation of quantum physics which is called the "Copenhagen interpretation", which, like many scientists including Einstein I should add, I think is erroneous. This is because it leads to such philosophical problems such as what is called the "measurement problem". Basically I and, even in the modern day, many scientists (although many mo ...[text shortened]... e will never ever go away for as long as thinking people exist who know of such interpretations.
    Interesting. It does sound like the only thing conventional quantum mechanics has over Bohmian mechanics is that it came first, has a lot of textbooks written about it, and is entrenched amongst the establishment. (Why change now? It's "work." ) This is because, it seems, the equations were written down nearly a century ago before anyone realized to what absurd conclusions they would lead philosophically, but they gained traction because they made good predictions. Well, Einstein caught on early, anyway. Everyone seems to despise the Copenhagen Interpretation, so I should think a theory that does away with it and yet makes the same predictions as quantum mechanics would be more readily embraced.

    Lee Smolin is right: there's something wrong with the way the physics community works and plays together. Really wrong.

    Crap, I'm short on time, otherwise I'd say more now.
  5. 18 Dec '14 19:01
    Originally posted by humy
    The conventional interpretation of quantum physics which is called the "Copenhagen interpretation", which, like many scientists including Einstein I should add, I think is erroneous. This is because it leads to such philosophical problems such as what is called the "measurement problem". Basically I and, even in the modern day, many scientists (although many mo ...[text shortened]... of Occam's razor which, although a perfectly valid principle, should be used with some caution.
    You may well be correct. I don't like the Copenhagen interpretation, either. But... that Frenchman's experiments (I keep forgetting his name, every time again... something with a couple of a's in, I think) does seem to indicate that at least the over-light-speed connectivity of quantum particles is true. I don't like that, either, but it does seem to be correct.
  6. 18 Dec '14 19:17
    Originally posted by Shallow Blue
    ... seem to indicate that at least the over-light-speed connectivity of quantum particles is true. I don't like that, either, but it does seem to be correct.
    Massless particles can only go *in* the speed of light, if I have understood it correctly.
    But if it doesn't contain information at all, then it can go any speed.

    This entanglement between particles - does this really contain information? No? Then it has no limitations at all. (Right?)

    Any with better insight can surely explain this phenomenon better than me.
  7. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    18 Dec '14 19:48
    Originally posted by KazetNagorra
    Bohmian mechanics is the most well-known attempt at a deterministic quantum theory. However, it is not that popular because, as far as I know, it doesn't do any additional empirically verifiable predictions compared to the orthodox interpretations.
    But the "orthodox interpretations" all include the Copenhagen Interpretation, yes? Which everyone seems to loathe except maybe for the mayor of Copenhagen.
  8. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    18 Dec '14 20:06
    Originally posted by humy
    I cannot help but have the suspicion that the Copenhagen interpretation has only become the most popular one because both many scientists and the public alike liked the weirdness of its implications rather than because of any real sound rational scientific reason although I can also see how the Copenhagen interpretation could come from a naive application of Occam's razor which, although a perfectly valid principle, should be used with some caution.
    I think you're on to something there. If you make the universe deterministic, it comes more mundane and there seems to be less room for magical-seeming paradoxes. An awful lot of laymen's books on quantum mechanics, as well as every television program ever broadcast on the subject, would start looking pretty damn foolish -- along with nearly all hands on board. Would it mean that so-called "classical" physics would be back in fashion? Would it mean that all probabilities associated with physical theories would be merely a reflection of what we don't know rather than something inherent in nature itself?

    But I don't see how the Copenhagen Interpretation could be the best conclusion based on an application of Occam's Razor.
  9. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    18 Dec '14 20:17
    Originally posted by humy
    It is an extremely common modern day misconception that quantum mechanics says quantum events are not determined but actually quantum mechanics doesn't specify whether quantum events are determined or not and the Copenhagen interpretation isn't the actual quantum mechanics but is rather purely a metaphysical interpretation of quantum mechanics thus quant ...[text shortened]... ics doesn't specifically say/imply a realist interpretation must be wrong nor merely improbable.
    Well, yeah, you have to leave room for an omniscient being to sit on a cloud and "know everything" -- that being an omniscient being's proverbial one job. I agree that the bare bones of quantum mechanics makes no comment on whether anything is predetermined or inherently probabilistic. It's still mechanics fer chrissake. But quantum physics as whole, of which quantum mechanics is but a part, does seem to lead to some wonky remarks about the nature of reality and existence. I mean, you have quantum theorists all over the place churning out ever crazier ideas about holographic universes, parallel universes, holographic parallel universes full of Klingons singing opera, and so on. If there isn't a skeleton in the closet underlying all this, then why are serious physicists so uncomfortable about it all when asked to give their interpretation of the theory?
  10. Standard member adam warlock
    Baby Gauss
    19 Dec '14 06:15
    Originally posted by Soothfast
    Interesting. It does sound like the only thing conventional quantum mechanics has over Bohmian mechanics is that it came first, has a lot of textbooks written about it, and is entrenched amongst the establishment.
    This view of yours is just too naive.
    BM is its orthodox form needs hidden variables and non-locality (since Bell's theorem proves that a local hidden variables theory makes different predictions than orthodox quantum mechanics and experiences have been made that vindicate the orthodoxy) and each of this assumptions alone is at least as dislikable as the orthodox interpretation of QM.

    If you're cup of tea is non-locality and the ad hoc introduction of variables which you don't know nothing about except the fact that they explain the word you see (even though you can't understand the whys and hows of) the Bohmian mechanics is just fine and dandy.

    My personal opinion is that neither the orthodox quantum mechanics (which is distinguish from the orthodox quantum mechanics) with its beautiful linear theory of operators nor the stitched up bohmian formalism is the way forward to understand reality at the quantum level. What we really need is an intrisic nonlinear descritpion of the quantum world.

    PS: Newton's theory of gravity is elegant and linear and neatly explains a lot of what we see in the world and one can stitch up a lot of ad hoc nonsense in top of it in order to explain some of the things that the original theory doesn't explain. Or we can just use a nonlinear theory of gravity (Einstein's General Theory of Relativity) which is at least as elegant as Newton's theory and has a lot more predictive and explanatory power.
  11. 19 Dec '14 08:16 / 6 edits
    Originally posted by adam warlock
    This view of yours is just too naive.
    BM is its orthodox form needs hidden variables and non-locality (since Bell's theorem proves that a local hidden variables theory makes different predictions than orthodox quantum mechanics and experiences have been made that vindicate the orthodoxy) and each of this assumptions alone is at least as dislikable as ...[text shortened]... h is at least as elegant as Newton's theory and has a lot more predictive and explanatory power.
    Newton's theory of gravity is elegant and linear and neatly explains a lot of what we see in the world and one can stitch up a lot of ad hoc nonsense in top of it in order to explain some of the things that the original theory doesn't explain.

    Newton's theory of gravity, unlike Copenhagen Interpretation of quantum mechanics, doesn't have the problem that it fails to explain such problems as the “measurement problem”.
    See http://en.wikipedia.org/wiki/Measurement_problem
    Thus, unlike with quantum mechanics, it is far from obvious what Newton's theory of gravity fails to explain that demands an explanation and there is no need to add extra hidden variables (or whatever ) to explain some kind of 'strangeness' of Newton's theory of gravity.

    Plus Newton's theory of gravity, unlike the Copenhagen Interpretation of quantum mechanics, isn't a metaphysical interpretation of some physics but is the physics itself (although, just like most/all types of physics, it makes some assumptions ). Copenhagen Interpretation is a metaphysical interpretation of quantum mechanics not to be confused with the quantum mechanics itself that doesn't say how it should be interpreted nor whether there are hidden variables etc.

    Personally I don't have a problem with the "spooky action at a distance". After all, we have such things as gravity, electric fields, magmatic fields etc that act at a distance. I also don't have a problem with quantum tunneling. It isn't those things that I am suspicious of.
  12. Standard member black beetle
    Black Beastie
    19 Dec '14 11:06
    Originally posted by Soothfast
    Well, yeah, you have to leave room for an omniscient being to sit on a cloud and "know everything" -- that being an omniscient being's proverbial one job. I agree that the bare bones of quantum mechanics makes no comment on whether anything is predetermined or inherently probabilistic. It's still mechanics fer chrissake. But quantum physic ...[text shortened]... physicists so uncomfortable about it all when asked to give their interpretation of the theory?
    QM requires reality to be discontinuous, non-causal and non-local whilst, according to relativity theory, reality is supposed to be continuous, causal and local. In order to come up with a resolution, Bohm suggested that the two contradictory theories have a common: Undivided Wholeness.
    Since, for one, non-locality is a fact and for two, under certain circumstances subatomic particles are able to instantaneously communicate with each other regardless of the distance separating them, Bohm suggested that there is always an interconnection between matter, and he postulated that instead of “particles” there is a huge undivided spherical standing wave in space. In other words, Bohm’s “Wholeness” is the whole observer universe, whose every bit of its matter is a Spherical Standing Wave in Space, which is neither static nor a collection of separate objects, but a dynamic ever changing nexus-in-flux (this dynamic nexus is Bohm’s Holomovement: “Holo” because reality is structured in a manner similar to holography, and “Movement” because reality is in a constant state of change and flux); to Bohm, subatomic particles do not contact with one another because of some mysterious interaction or “spooky action”, but because their separateness is an illusion

    And Bohm insisted that the observer universe is like a hologram because its dynamic flux is caused by a single continuously connected wave medium;
    There, a skeleton in the closet
  13. 20 Dec '14 05:26
    Originally posted by Shallow Blue
    ... that Frenchman's experiments (I keep forgetting his name, every time again... something with a couple of a's in, I think)
    Alain Aspect
  14. 20 Dec '14 13:19
    Originally posted by Paul Dirac II
    Alain Aspect
    Thanks, that's the one.
  15. 20 Dec '14 15:06
    Originally posted by humy
    Newton's theory of gravity is elegant and linear and neatly explains a lot of what we see in the world and one can stitch up a lot of ad hoc nonsense in top of it in order to explain some of the things that the original theory doesn't explain.

    Newton's theory of gravity, unlike Copenhagen Interpretation of quantum mechanics, doesn't have ...[text shortened]... also don't have a problem with quantum tunneling. It isn't those things that I am suspicious of.
    Actually, EM fields don't act at a distance (photons carry it). Gravity probably not either, although we have not directly measured the carriers of the gravitational force.