Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Delayed choice quantum eraser

  1. May 13, 2008 #1
    The paper described at http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser rather intrigues me.

    While the results appear counter intuitive to us, the properties being tested are those of light, and since light travels at speed c, is it not the case that for light time stands still. If so, is it not the case that the light travelling all the different paths is one and the same thing, and since our time does not exist for a photon, it doesn't have our personal confusion about notions involving past and future. If so is not the outcome explained by saying that light behaves a certain way when in a certain collective spatial state (time not governing its behaviour), as set up as a consequence of the experiment. That is, might not the randomness of partial reflection be viewed as conditioning the outcomes observed for the collective spatial state of the light, and at the same time conversely the outcome be viewed as conditioning the randomness that we observe in the path the light takes as a consequence of the partial reflection.

    Another way of thinking about the same issue is that the light leaves the source and arrives at the destination according to its frame of reference in no time. We however say that time has passed. Can we not argue that the relationship between our notion of time and the photons notion of time impacts upon the experiment being performed, and that the photons clock as we perceive it is moving backwards in time "relative" to ours since its clock is not ticking. In what sense might this relative backwards in time phenomenon, manifest itself to us as appearing backwards in time communication.
    Last edited: May 13, 2008
  2. jcsd
  3. May 14, 2008 #2


    User Avatar
    Science Advisor

    For an intuitive "explanation" by an analogy from everyday life see
    https://www.physicsforums.com/blogs/demystifier-61953/quantum-weirdness-in-everyday-life-ii-1460/ [Broken]
    This analogy is inspired by the Bohmian view of quantum mechanics, in which delayed choice quantum eraser is not counterintuitive at all.
    Last edited by a moderator: May 3, 2017
  4. May 14, 2008 #3
    Thanks.. interesting.. sort of moves the problem to how do photons put on and take off shirts. The analogy also avoids the issue of how do photons which are not in the same time zone (from our perspective -- they probably are from theirs if photons are permitted perspectives) collectively form the social groups they do.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook