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If we could see 13.7 Billion lyears away?

  1. May 11, 2010 #1
    The age of the universe is approx 13billion years right?
    (if not, sub the correct value for everytime i say 13billion)

    I was wondering.. if we could, in theory, see something 13billion light years away
    we would see it how it was that long ago right?
    So would we not see the big bang?

    This may well be impossible, just an interesting thought.. i thought..
    If we could see something that far away, would we see the big bang?

    I posted this on here in hope of a more educated answer?

  2. jcsd
  3. May 11, 2010 #2


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    You're right that when we look at very distant objects we look very far back in time. However early on the universe was opaque to electromagnetic radiation and it took approximately 380,000 years for the universe to become transparent to electromagnetic radiation. That means we can't look further back than 380,000 years after the big bang. Not by detecting photons anyway.
  4. May 11, 2010 #3


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    Yes, it looks like http://en.wikipedia.org/wiki/File:WMAP_2010.png" [Broken].
    For a disclaimer (actually, we can't see exactly the big bang, but the state of the universe 380000 years later), see https://www.physicsforums.com/showthread.php?t=401866".
    Last edited by a moderator: May 4, 2017
  5. May 11, 2010 #4
    Ah so this IS the cosmic background radiation i hear about in lectures :)
    Thank you very much guys!
  6. May 11, 2010 #5


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    With a neutrino telescope, we could theoretically see back almost to the main event. Unfortunately, such a telescope would require an aperature of many light years to achieve useful resolution.
  7. May 12, 2010 #6
    Can we see further than -age of the universe- light years away?
    (in any part of the electromagnetic spectrum?)
    Does the exapansion of the universe enable this?
  8. May 12, 2010 #7
    I think it would be helpful to have a better understanding of the terminology used for "Big Bang" since the OP RCulling asked, "So would we not see the big bang?" Briefly, here are the observations that have been made.:biggrin:

    Last edited by a moderator: May 4, 2017
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