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Does the act of observing/measuring define an arrow of time?

  1. Feb 8, 2014 #1
    i was just reading the following article and had an interesting thought; http://www.ipod.org.uk/reality/reality_arrow_of_time.asp [Broken]

    Referring to the following image (http://www.ipod.org.uk/reality/reality_arrow_of_time.asp [Broken])

    Both Feynman diagrams are said to be mathematically equivalent. The left describes an electron the emits a photon and experiences a recoil in its direction of propagation through space corresponding to momentum lost. the diagram on the right describes a photon that changes to a positron (electron moving backward in time) and an electron.

    Is it possible to interpret the diagram on the right as a photon that collides with an electron moving backwards in time (positron) and the recoil sends the positron flying forward in time (converting it to an electron)? say, the photon resembles an 'observation' or 'measurement'. assuming this interpretation is sound, could it be that the act of observation/measurement, be it from the environment or a human apparatus, be the reason for the apparent 'flow of time' that we experience ? what are your thoughts? (its not a fully developed idea, just a thought!)
    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. Feb 8, 2014 #2
    Yes, but that would be an interpretation. Interpretations are interesting, but only useful if they tell us something new.
  4. Feb 8, 2014 #3
    so you mean to say that this interpretation could not and would not tell us anything new?
  5. Feb 8, 2014 #4


    Staff: Mentor

    That fact about Feynman diagrams is well known.

    And no, that it can be viewed that way tells us nothing new. It may make understanding some things easier, more elegant, etc etc, but telling us something new - that's another matter.

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