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Speed of light

  1. Apr 15, 2006 #1
    Just read about the advances on travelling at the speed of light. I have a problem about the whole "time travelling" theory. If (or maybe when) the human race can travel at a speed faster than time itself, how could we possibly go back in time? Surely going faster than time would mean that you would only go forward and not back in time?
    Perhaps we could travel slower than time. A negative speed would be much harder to obtain than a possitive speed surely.
    I know that you are the people to explain to me ( please be nice) about this.
  2. jcsd
  3. Apr 15, 2006 #2


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    Gold Member

    I'm not sure about the specifics, but time travel can occur within a kind of (closed)feedback (time)loop where backwards movement is possible.

    There is a book by Stephen Hawking called The Universe in a Nutshell where he discusses time travel. Very good read to gain a basic understanding about the difficulties about time travel.

    Last edited: Apr 15, 2006
  4. Apr 15, 2006 #3


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    Staff Emeritus
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    OK, what did you read, and where? It sounds like you read something that was a bit garbled, because, for starters, you can't travel at the speed of light.
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