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Collapse and creation of wave function

  1. Aug 13, 2011 #1
    in a double slit experiment, if we find which-way and then stop observing the photon and send it again through another double slit (kept in, say, series), would an interference pattern occur?....the second time around
  2. jcsd
  3. Aug 13, 2011 #2
    If I am envisioning your thought experiment correctly, then yes.

    Just to make sure I'm visualizing the same thing, you're talking about letting the photon pass through a detection screen, then through a second double slit, then to a second detector, you should be able to get a second interference pattern, in theory, as long as the experiment is set up correctly.
  4. Aug 13, 2011 #3
    thanks CJames. so in the first screen there would be no interference pattern (because we got which-way) however the second screen would have the interference pattern.

    so getting which-way causes the photon to behave as a particle but only for a short period of time, when we are observing the photon?
  5. Aug 13, 2011 #4
    When we have determined the path of a said photon then we observe that it behave particle like i.e for example if one photon has gone through a slit we'll see a point on the screen ahead however say if haven't observed the wave-function of the photon then an interference pattern is observed. Yes,for a short period as long as the observer is inciting a collapse.

    Have a read on Schrodinger's "Cat in a box" experiment[ C.I] which explains quantum behavior adequately and HUP.When we know the position of a particle with greater precision then this induces greater uncertainty over the momentum parameter, as a result of this we find ourselves being able to calculate one parameter but this irrevocable changes other.

    Last edited: Aug 13, 2011
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