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Measuring the universe ?

  1. Jun 6, 2010 #1
    Is it possible to measure the supose end of the universe with a wave that will bounce of the end of the universe and return ?
  2. jcsd
  3. Jun 6, 2010 #2


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    Staff: Mentor

    Welcome to PF.

    The universe does not appear to have such a boundary.
  4. Jun 7, 2010 #3


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    A light wave that we emitted today would not be able to return from the most distant things we can see today. Basically, we can see the ancient light that these things emitted long ago, but in the mean time they've moved so far away that we'll never be able to see the light that they emit today.
  5. Jun 7, 2010 #4
    the universe is constantly expanding. such a boundary is always getting larger and by the time we see it, the universe is already larger than what we saw it as. many of the claimed of the size of the universe are estimates because how can we see more than 15 billion light years away.
    hope this helps, BT
  6. Jun 7, 2010 #5
    Lawrence Berkeley National Laboratory has a fine video glossary. Astrophysicist David Schlegel explains about measuring the universe. You can view the video online.:biggrin:
    http://videoglossary.lbl.gov/2010/measuring-the-universe/ [Broken]
    Last edited by a moderator: May 4, 2017
  7. Jun 8, 2010 #6
    Great Video
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