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Quantum Observer Effect, Help Me Understand.

  1. Feb 19, 2012 #1
    My question is about the Quantum Observer Effect. I know in the double-slit experiment originally my mind was set that somehow the measuring device altered the experimental variables but in light of a recent experiment where all possibility of that was null I am again at point zero with this theory. What exactly constitutes an "observer"? Is it simply the act of measurement before the results have manifested? And I hear respectable scientists throwing the word "conscious observer" around, so are we still in the age of considering consciousness some kind of metaphysical force? Is it just because of our limitations in time and we are only able to actively observe a part of the wave function instead of the whole "observation collapses wave-function" idea?

    Probably a long question with a simple answer, but it's been bothering me.
  2. jcsd
  3. Feb 20, 2012 #2
    Hi! AFAIK, the common view is still that "observation" is the same as "measurement" in quantum mechanics, see e.g. Observer (quantum physics). In the double-slit experiment this corresponds to placing a particle detector at the slits, and we need not to consciously observe it.
    Which experiment are you referring to?
  4. Feb 20, 2012 #3
    It is pretty hard to tell what causes a 'measurement' to occur. QM predicts no collapse of the wave function. The particle simply entangles with the measuring device.
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