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Breaking the speed of light?

  1. Apr 21, 2009 #1
    2 objects are traveling in opposite directions from each other with more than 0,5c. Would an observer watching them perpendicular to their trajectory see that they are moving faster than c away from each other, or is there something that will "stop" this?
  2. jcsd
  3. Apr 21, 2009 #2


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    Staff: Mentor

    IN that observer's reference frame, the two objects' separation does increase at a rate greater that c. Relativity does not prevent the rate of separation of two objects in a third reference frame from being greater than c.

    What relativity does prevent is each object going faster than c in the other object's reference frame.
  4. Apr 21, 2009 #3
    Thanks, that was exactly what I was uncertain about. You answered my question in the best possible way.
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