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I Doesn't wave duality for massive objects favor pilot-wave?

  1. Feb 24, 2017 #1
    It is well known that wave particle duality was also observed with large particles up to 10000 amu:

    Abstract of Paper : https://arxiv.org/abs/1310.8343

    Doesn't that make pilot wave theory a more logical interpretation? For example it is easier than the whole material becoming a wave (regardless of your favorite definition of that wave).
  2. jcsd
  3. Feb 24, 2017 #2


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    Why would it be more logical? If the fundamental particles are already waves, then it seems to make perfect sense for the composite particle to also be a wave.
  4. Feb 24, 2017 #3
    I would agree that it is more logical for a wave to behave like a wave than for a particle to mysteriously start being a wave.
  5. Feb 24, 2017 #4
    But they say that this can also apply to macroscopic objects like viruses or cells (I am not sure about the credibility of such claim). If that is true then can a virus be a wave also?!
  6. Feb 24, 2017 #5
    Yes if an experiment is designed to measure such behaviour.
  7. Feb 24, 2017 #6
    Can we do it with baseballs too? What is the limit?
  8. Feb 24, 2017 #7


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    Well wave particle duality was done away with early on in QM.

    I have recently been reading an interesting book about Einstein:

    When De Broglie proposed it Einstein knew it was wrong, but a very important step in elucidating the quantum puzzle.

    Schrodinger was challenged that if particles have wave aspects then it must have a wave equation. He found one - Schrodinger's equation - but goofed - his derivation was erroneous:

    But then things rapidly progressed and Einsteins intuition was proven correct - as was usually the case. It was done away with at the end of 1926 when Dirac came up with his transformation theory the combined Schrodinger, Heisenberg, and even the lesser known Dirac q numbers approach, into the one theory, the tranformation theory, that generally goes by the name QM today:

    Schrodinger was disgusted, and wished he never became involved with the whole thing. Einstein thought it wrong and started a crusade to prove it wrong - but failed - admitting at the end it was correct, but till his dying day believed incomplete ie an approximation to an even deeper theory that conformed more to his intuition about the world. The thing about Einstein is he was amongst the greatest - people with amazingly quick minds that dazzled everyone - people like Von-Neumann and Feynman. They were much better mathematicians, and had far greater technical ability than Einstein. What set him apart was his ability to penetrate to the heart of a problem. In that he was unmatched. He saw straight away wave-particle duality was wrong - but struggled til his dying day to find out what was right and appealed to his intuition on how the world worked. Will he be proven right in the end - it hard to bet against a man like him.

    Last edited by a moderator: May 8, 2017
  9. Feb 24, 2017 #8


    Staff: Mentor

    Its only technological - we can do it with molecules containing 800 atoms:

    But - it's not wave particle duality they are demonstrating - its simply quantum behavior that is similar to waves. As I said wave particle duality is wrong, and was realised as wrong by no less a person than Einstein when first proposed - but a very important advance none-the-less that was part of the final resolution of the quantum puzzle - just as Einstein's intuition said it would be. I think his words were something like it has lifted one small corner of how nature works.

  10. Feb 25, 2017 #9
    Thank you for this answer. The problem is that the term wave-particle duality is one of the most widely used concepts in QM.

    But what is the alternative explanation that you can offer? you used an obscure description "it is wave like", the standard model says it is just a wave of probabilities, some physicists insist that it is a real wave:
    When talking about single photon or electron, I can digest the idea that the particle can behave like a wave (maybe it was a wave all the time), but when talking about massive object this concept became very hard to digest, I was never a fan of Pilot-wave theory (because I think it is incomplete and was not tested extensively), but when I was thinking about the particular case of a massive object behaving like a wave, pilot-wave theory offered an elegant solution that clicked for me!

    I imagine deep in my thoughts that part of pilot-wave is true, and part of the standard model is true. Maybe one day someone can combine both of them in one elegant theory.
    Last edited: Feb 25, 2017
  11. Feb 25, 2017 #10
    Well, it's quantum mechanics itself. There is no wave-particle duality in QM.
  12. Feb 25, 2017 #11


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    Bear in mind that a photon is massless but electrons and protons and suchlike have mass. We know that light interferes with light, but, as you say it is hard to imagine how a solid body 'interferes'.

    My own belief is that the masive particles are not and cannot be waves, nor do they need to be. It is the formulae we use to calculate probabilities ( in the absence of good localization data) that have wavelike properties.
  13. Feb 25, 2017 #12


    Staff: Mentor

    Only in popularizations and beginning texts. Intermediate or advanced texts never use it. For example you will not find it in Ballentine which is my and many others standard reference.

    I gave the full answer, including its history, and when it was done away with, in post 7.

    Wavelike is what the free particle solution to Schrodinger's equation is called. But normal waves are not complex, nor are they so called waves of probability ie they are actual 'stuff'.

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