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Question About Light From the Big Bang

  1. Jun 17, 2012 #1
    I was watching a video on Youtube about the Big Bang, and they said something that I did not understand. They said light from the big bang can still be seen from the Earth in the form of microwaves. I understand, however, that nothing travels faster than light. So how did our earth come to its point in space before light reached that point?

    I am clearly a newbie, sorry.
  2. jcsd
  3. Jun 17, 2012 #2


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    They are talking about the cosmic microwave background [CMB] which was emitted from the surface of last scattering about 380,000 years after the big bang. Prior to that time photons could not travel freely throughout the universe. Due to the expansion of the universe those photons are just now catching up with us. While ordinary matter is forbidden from travelling at superluminal velocities, space is not forbidden from expanding superluminally.
  4. Jun 17, 2012 #3
    Thank you, Chronos!
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