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Einstein's Twin Paradox

  1. May 27, 2004 #1
    say the rocket had a engine, which produced to get the rocket to go at the speed of light but then it ran out of fuel and the rocket would slow down. what would be the age difference between them? say both were 24 one on earth and one on return journey from a nearby star system.
  2. jcsd
  3. May 27, 2004 #2


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    Staff: Mentor

    That isn't even close to being a coherent thought. Could you try again please? The one part that made any sense - the part about the rocket slowing down - is wrong. Rockets do not slow down in space without engines firing to slow them down.
  4. May 27, 2004 #3

    ok so what if the there were engines that fired to slow them down?
  5. May 27, 2004 #4
    Well, your question is kind of sketchy, but if im reading it right...
    since light has no notion of time (time freezes when you are travelling the speed of light), the space ship in space would be equal to 24 (it would remain unchanged, and the space ship on Earth would have continued aging at a normal rate...
  6. May 27, 2004 #5
    cheers mark
  7. May 27, 2004 #6


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    Does the spaceman come back to Earth to compare ages ? You don't specify which frame you are measuring in ? Are you asking because you want to know...or because you want to see what other people know ? In other words, is this a doubt or a brain teaser ? The latter does not belong here.
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