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Time vs Light question

  1. Jan 1, 2004 #1
    alrighty brainiacs... I love all this stuff but I'm still a newbie. I was watching a show on the Science Channel which stated that our Universe is not only expanding, but accelerating infinitely. Old news, I know. So, a question popped into my head. Maybe this is simple and I just don't get it. Hope I can explain it.

    okay.. here goes..

    If the Universe (space-time) is accelerating infinitely, what happens when the speed of space-time itself reaches the speed of light, which is in theory the fastest thing going?

    Does everything go haywire and start a new big bang? Or can the speed of accelerating space-time actually reach the speed of light at all?

    - Joe
  2. jcsd
  3. Jan 1, 2004 #2


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    Spacetime itself can expand "faster than the speed of light" because the expansion isn't a speed. Nothing can go through space faster than light, but spacetime isn't going through itself, it's expanding - different thing, different laws of nature apply. Relative to us, some of the distant galaxies that we can see are "receding faster than light". Actually it isn't their motion, it's the space between us expanding.
  4. Jan 1, 2004 #3
    See? I knew I came to the right place. Pretty bizarro stuff. Thanks!
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