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The Human Double Slit Experiment

  1. Dec 19, 2013 #1
    Okay it's been well established that objects with momentum exhibit wave like properties. Hence, electrons being observed forming interference patterns when scattering off of crystal lattices. Also I recently read this webpage. At the bottom it mentions performing a double slit experiment with cats firing them haphazardly at two slits to see if they interfere. Now obviously it wouldn't work in any normal sense. But it mentions a lot of little technicalities, one obvious one for me is that the de Broglie wavelength of any object comparable to humans would be comparable to Planck's constant, so extremely tiny slits would be needed (correct me if I'm wrong). My question is what are those other "technicalities" mentioned. Also it says that you would need to space out the firing of the cats in a time interval longer than the age of the universe, I just plain don't understand that bit, why do you need to space out the firings for larger objects that much? I figured as long as you waited until one already hits, that would be good enough. Any clarification is welcomed.
  2. jcsd
  3. Dec 19, 2013 #2


    Staff: Mentor

    Its the decoherence thing. For macro objects to show quantum behavior they need to be isolated from the environment which, to put it mildly, is VERY VERY hard to do eg it would need to be cooled to near absolute zero.

    The spacing out thing may be that the slits would need to be so small it would take a huge amount of time for a cats wave-function to leak through - just a thought off the top of my head.

    Last edited: Dec 19, 2013
  4. Dec 19, 2013 #3
    Maybe the author is trying to say that:

    The speed needs to be really slow, so as to reduce the momentum -- so that the wave-length is long enough?....for interference effects to show up.
  5. Dec 19, 2013 #4
    I thought it was fairly clear that he meant the time in between firings.

    Thanks for both of the answers, I'm starting to get it now. Or at least I think I am :)
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