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Will light get reflected at edge of space

  1. Oct 23, 2013 #1
    What happens when light gets to the edge of space or universe, does it get reflected back.
    Assuming that light gets reflected back at the edge of universe. We are seeing the reflections of the same star galaxy, at different points of time, at different location. Since the reflected photons travel a greater distance than the photons of the real object, the reflected photons would be of lower frequency when compared to the light from the actual object.
    So if we eliminate all the reflections from actual direct light of stars (luminous objects), would the size and mass of the universe that we intepret as of now, be smaller than what we perceive.
  2. jcsd
  3. Oct 23, 2013 #2


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    There is no "edge of the universe" for light to reflect off of.
  4. Oct 23, 2013 #3
    There is no edge. One possibility that has been considered in the literature (Highly unlikely in my opinion) is that of a universe with periodic boundary conditions in which case it would be possible to travel all around the universe back to your starting position without ever taking a turn (kinda like circumnavigating the globe). That possibility could create multiple images of distant galaxies. But alas, there is no evidence that our universe has periodic boundaries.
  5. Oct 23, 2013 #4


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    We are at the temporal edge of the universe - the oldest place in all of the heavens. You cannot get more distant from the Big Bang than here. Do you see any weird reflections? Once a light beam whizzes by earth, it travels into our future. We can't see reflections from the future, only the past.
  6. Oct 27, 2013 #5
    doesn't that depend on whether or not there are boundary conditions?
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