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Planck Epoch

  1. Oct 29, 2005 #1
    I draw a straight line representing the time line of the universe. On this line I put a mark at 1cm and I say this represents the end of the Planck Epoch. So I can understand how tiny the Plank Epoch was, could someone tell me, how far along the line at this scale the first second of the universe would appear.
    I imagine it would fall quite a distance along the line.
  2. jcsd
  3. Oct 29, 2005 #2


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    The Planck epoch ends at 10-43 sec. after the big bang.
    So if that time interval is represented by 1 cm. the line out to I second will be 1043 cms. long. Now OOM the Hubble radius, crudely the radius of the observable universe, is 1028 cms.

    So your line will be 1015 times longer than the furthest distance we could possible see in the observable universe!

    Does that give you an idea how short the Planck era is? :smile:

    Last edited: Oct 29, 2005
  4. Oct 30, 2005 #3
    Thanks for that. I never realised it would be that much! The Planck Epoch truly is tiny and amazing to contemplate.
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