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Does an observation now create the past?

  1. Apr 21, 2012 #1
    Fred Alan Wolf in his book Star Wave - Mind, Consciousness, and Quantum Physics talks about an experiment similar to the double slip experiment where light is a wave when not observed and a particle when it is observed. This one has light coming from a distant quasar with a galaxy between the earth and it. The gravity of the galaxy (G-1) bends the light in accordance with Einstein's theory of general relativity. In this case there are two paths the light takes to earth, one taking 50,000 years longer to get to earth. The outcome of the experiment is like the double slit one. Whether the light took two paths or one depends on the observers choice to measure which path it took, or to measure the phase shift. He says that the path the photons took 50,000 years ago was instantly decided by the observers choice. ... "We create history now." Do you agree with that interpretation? Do you have another explanation?
  2. jcsd
  3. Apr 21, 2012 #2
    What you are describing is Wheeler's delayed choice thought experiment. Here is a description of how different interpretations of quantum mechanics deal with it. And here is an animation of it (rollover the image to see the picture change). I think discussion of quantum experiments and their significance belongs in the Quantum Physics forum.
  4. Apr 21, 2012 #3


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    Staff: Mentor

    This thread certainly doesn't meet the criteria for posting in Philosophy. The op didn't bother to read the rules. It will be up to the physics mentors if they want to move it.
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