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Big Bang misconception

  1. Dec 13, 2011 #1
    It's generally accepted that nothing can travel faster than the speed of light (expect hypothetical particles that have yet to be discovered). This is in accordance with general relativity.

    However general relativity seems to break down momentarily after the big bang because matter must have been accelerated at speeds greater than the speed of light during the rapid expansion phase.

    So surely general relativity is wrong because this matter must have exceeded the speed of light?

    Can anyone clarify this please?

  2. jcsd
  3. Dec 13, 2011 #2
    To illustrate this effect imagine you are measuring the distance between two objects with a measuring rod for several times and get an increasing distance. In classical mechanics this means that the objects are moving. But in GR there is another possibility: Your rod is shrinking. That's what happens with our universe. The metric of space is changing with time and there is no limit for this kind of expansion.
  4. Dec 13, 2011 #3


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    Matter wasn't accelerating. Space itself was expanding and carrying matter with it.
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