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I MWI proven wrong by penning trap experiments?

  1. Mar 17, 2017 #1
    Just a reminder to you all, I am just a layman...
    These experiments were both done is what is called a penning trap.

    I think this only proves the version of MWI where the universe doesn't actually split. The "bare" theory, where no new matter is created.

    According to MWI an electrons properties, including charge and mass, are spread out along the wave function. The universe doesn't split when making a measurement, and so conservation laws are not broken. However when a particle wave decoheres, all the different parts of its wave function split up and cannot interfere anymore. And that includes its properties like charge and mass, they also split up when measured. So when they did these experiments the particles positions were detected, and according to MWI the part of the electron in OUR state of the universe only has a fraction of the total charge and mass of the entire electron. However when they did the experiment they found that the electron has a full unit of charge and mass. This shows that MWI bare theory is wrong.
    What do you guys think? Am I wrong? Please give me your opinions, since I'm probably wrong.

    Heres the experiments

    https://link.springer.com/chapter/10.1007/978-3-540-39664-2_1

    http://iopscience.iop.org/article/10.1088/0031-8949/1988/T22/016/pdf
     
  2. jcsd
  3. Mar 17, 2017 #2

    PeterDonis

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    No, they're not.

    No, they don't.

    Yes. See above.
     
  4. Mar 17, 2017 #3
    You're wrong. The entire point of psi ontic interpretations is that the wave function is a literal description of reality. According to these interpretations, all of the particle's properties, are distributed throughout the wave function. And this is even true in bohmian mechanics (properties are not localized on the particle).
     
    Last edited: Mar 17, 2017
  5. Mar 17, 2017 #4
    You should look up "GRW Mass Density". The same rules apply for all psi ontic interpretations. And instead of just saying that I am wrong, you should at least explain yourself. However, I already have a feeling that you have no idea about what you are talking about.
     
    Last edited: Mar 17, 2017
  6. Mar 17, 2017 #5

    PeterDonis

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    Yes. But that does not mean that all of the properties of the electron, including its charge and mass, are "spread out" over the entire region of the wave function as you claim. If you think it does, please provide a mainstream reference (textbook or peer-reviewed paper) that supports your claim. Pop science sources are not acceptable.

    You are aware that the GRW theory is a collapse theory, right? The MWI is a no collapse theory (more precisely, an interpretation, since, unlike the GRW theory, it only uses the standard math of QM).

    The GRW theory is not an interpretation of QM. It's a different theory, since it uses different math and makes different experimental predictions from standard QM. (The differences are not testable with our current technology, but they're still there.)

    You asked:

    That is what I did. And it seems rather inconsistent of you to admit that you are probably wrong, but then be so sure that I am wrong when you have admitted you're just a layman.

    If you want more explanation, it might help if you would say where you are getting your understanding of the MWI from. What textbooks or papers have you read?
     
  7. Mar 17, 2017 #6
    "Bohm particles and their detection in the light of neutron interferometry"
    Here is an article explaining how in bohmian mechanics, the physical properties of the particle are spread out over the wave function and not localized on the particle. And, the math does say that the wave function does infact give you the mass and charge density. If you take the wave function as real, than the mass and charge density is real. And if you ask any advocate of MWI, they will tell you that everything about the particle (including its properties) are spread out.
     
    Last edited: Mar 17, 2017
  8. Mar 17, 2017 #7
    I shouldnt have said that I am a layman, since I am a physics student at Rutgers. I have asked my QM and EM teachers, whether the properties like charge and mass are localized or spread out, and they all agree that they are infact spread out throughout the WF.
     
  9. Mar 17, 2017 #8

    PeterDonis

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    Link, please?

    When you take appropriate expectation values, yes. But that's not enough to justify the claims you are making.

    Again, can you give a reference--textbook or peer-reviewed paper--that supports this? And shows, mathematically, what is meant by it? I strongly suspect that if you find such a source, you will see that the mathematical meaning of "spread out" in this connection does not justify the claims you are making based on it.

    Do your teachers say that the penning trap experiments you reference disprove the MWI?
     
  10. Mar 18, 2017 #9
    https://link.springer.com/article/10.1007/BF02055211
    Here is the article (I have bought the article, however it will not let me link it for some reason so you can only read the abstract). And you can email MWI advocates such as Matt Strassler and Don Lincoln, and they will tell you that everything about the electron is spread out. What are your qualifications?
    And here's Arnold Neumaier's paper on the topic. http://www.mat.univie.ac.at/~neum/physfaq/topics/touch.html
     
  11. Mar 18, 2017 #10
    And it is enough to justify my claim. You should look up protective measurement and how it shows that mass and charge are distributed throughout the wave function.
    But for now please stop replying on this thread, I rather have some one who has answers rather than someone who doesn't even seem to know basic QM.
     
  12. Mar 18, 2017 #11

    PeterDonis

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    Do they say that the penning trap experiments you reference disprove the MWI?
     
  13. Mar 18, 2017 #12
    No I never asked them, and I didn't get a chance to ask my teachers yet. But when my spring break is over and school starts back up I can show them the articles, but they may be too busy to look at them.
     
  14. Mar 18, 2017 #13

    PeterDonis

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    I'm aware of protective measurement. As I understand it, the point of protective measurement (which is the kind of measurement being done in the penning trap experiments, as far as I can tell) is to be able to obtain information about a quantum system's state (from a pointer variable that gets correlated to it) without changing that state. But if the system's state does not change, then neither would the probability density distribution of its wave function, and therefore neither would the mass or charge density.
     
  15. Mar 18, 2017 #14

    Nugatory

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    Something is wrong with your understanding of MWI, because that's not what it predicts.
     
  16. Mar 18, 2017 #15
    Why bother asking us, if you're just going to question answers given by experts in their field on here?
     
  17. Mar 19, 2017 #16
    When they are measuring the magnetic moment, and angular momentum, are they doing this by locating the electron? Does the electrons positional wave function collapse or is it still uncertain?
     
  18. Mar 19, 2017 #17

    PeterDonis

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  19. Mar 19, 2017 #18

    PeterDonis

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    Since the OP has opened another thread on this same topic, this thread is closed.
     
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