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This cant be true

  1. Oct 17, 2011 #1
    This cant be true!!!

    This guy is talking about collapsing a wave function by just looking at it with your naked eye. This cant be true. When he refers to big eye, small blurry eye hes making a metaphor right? The person and the eye are the measuring device correct? Im going crazy this cant be true. People cant just look at double slit experiments and make them collapse!!!

    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Oct 17, 2011 #2


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    Re: This cant be true!!!

    Don't get crazy. Easy... As I already explained you in another thread: as long as you don't define precisely what do you mean (in terms of observables) by 'collapse', you can't talk about it responsibly. No such definition of 'collapse' is commonly accepted, so all such discussions always sink in metaphores and misunderstandings.

    For me 'collapse' (for those rare situations I use this word) is caused not by a naked eye, but by hand equipped with a pencil.
  4. Oct 17, 2011 #3
    Re: This cant be true!!!

    Did you watch the video? Im talking about getting two bands of light instead of several. Im schizophrenic and this guy is telling me that my "counciess" knowledge of what slit the electron went throught after observing it with my naked eye causes the wave function collapse!! I thought it was the electron/ photon interaction that causes the collapse not the "knowledege" of which slit the electron went through, its just a convinient coincidence that any electron/photon interaction that provides measurable date collapses the wave function not the "knowledege" of which slit the electron went through.
  5. Oct 17, 2011 #4


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    Re: This cant be true!!!

    Frankly: I got bored after first 2 mins...

    All the answers (consciousness, eye observation, apparatus measurement, first photon/electron interaction, many more) may be correct for their respective meanings of 'collapse'. If you use 'collapse' to a measure of your knowledge about the process - I won't be worried by statements that 'collapse' is caused by naked eye observation, reading of experiment report made by someone else, receiving a phone call, etc.

    As long, as you don't associate any metaphysical meaning to the 'collapse' - there is nothing weird in it.

    If you are worried by 'collapse' caused by naked eye, phone conversation or planet positions at the moment of experimenter's birth, answer yourself basic question: "how may you distinguish between particles ruled by collapsed wavefunction and a noncollapsed one?"

    I see you may got confused by mixing two meanings of 'collapse':
    1. operation on the wavefunction, replacing it with eigenstate, as an effect of our knowledge of measurement outcome;
    2. 'real' physical interaction (like photon scattering on the electron) - which changes the process, and which leads to change of its further behaviour, which may be described by replacing the wavefunction with its eigenstate.
    Last edited: Oct 17, 2011
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