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Wheelers Delayed Choice Experiment?

  1. Oct 17, 2011 #1
    "I was convinced that light must be causing the collapse of wave function, but Wheelers Delayed Choice Experiment seems to have confirmed otherwise. We can determine the state of a particle (ie wave or point) by choosing to observe, even if the decision about whether or not to observe is made well after the particle has past the point at which the observation was pointed. My explanation isnt great, but check it out."

    So what does this exactly say about the observer effect? I mean were not talking about counsciess time travel here are we?
     
  2. jcsd
  3. Oct 17, 2011 #2

    xts

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    Whom are you quoting?
    And what version of Wheeler's experiment you refer to?
    Nothing really.
     
  4. Oct 17, 2011 #3
    "I was convinced that light must be causing the collapse of wave function, but Wheelers Delayed Choice Experiment seems to have confirmed otherwise. " Im quoting somebody form a diffrent physics forum. Here he suggests that it isnt the photon/ electron interaction that causes the wave function collapse? That cant be true.
     
  5. Oct 17, 2011 #4

    xts

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    Why do you think so?
    If you want to discuss it deeply, you should define what do you mean as 'collapse'. As it is not quite clear and many people use the same term in different meanings. And what even worse - some people say that they accept some definition of this term, but then extend its meaning with their metaphysical baggage.

    As no one ever proposed any experimental test if the function is collapsed or not, for my Occamian-positivistic-reductionist nature 'collapse' should be thus used only as a description of mathematical procedure you apply during analysis of the evolution of some system. It is a measure of your knowledge, but do not affect any reality. Like substituting a variable in some equation with actual value. Or reducing an algebraic expression.

    But some people assign some real meaning to the 'collapse' - they say the 'collapse' alters the reality, although they do not explain how this alteration may be revealed and what is the nature of this alteration. For me it is an empty, meaningless metaphysics.
     
    Last edited: Oct 17, 2011
  6. Oct 17, 2011 #5
    The double slit causes the interference pattern to collapse based of the photon/electron interaction orrect? Does this also apply to the wheeler delayed choice experiment or is there some incosistencie?
     
  7. Oct 17, 2011 #6

    xts

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    I would not call it 'collapse' but rather that interaction between photons and electrons change electrons transverse momenta, thus making them angularily incoherent and in effect spoiling interference pattern. The word 'collapse' is not needed at all - it only brings its metaphysical baggage to discussion and blurs it with ambiguous meanings.
     
  8. Oct 17, 2011 #7
    thanks I agree but what does "I was convinced that light must be causing the collapse of wave function, but Wheelers Delayed Choice Experiment seems to have confirmed otherwise," this mean in terms of what causes the spoiling of the interference pattern in the wheeler experiment.
     
  9. Oct 17, 2011 #8

    xts

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    I don't understand that statement. Better ask this question to the person who posted it... Don't ask me for exegeses of other forum members thoughts, especially if I don't share (or don't understand) their points.
     
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