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Twin paradox and time

  1. Sep 14, 2014 #1
    A person in the earth (stationery frame) observes the clock in the spaceship (which almost moving at the speed of light) runs slow right? and an astronaut in the space-ship observes the clock in the earth, to him the clock also appears slow the same rate as the person observes the clock in the spaceship right? Then how does the Twin Paradox works?
  2. jcsd
  3. Sep 14, 2014 #2


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    Try a forum search. That's only been discussed here about a thousand times.
  4. Sep 14, 2014 #3
    You haven't got to the "paradox" bit yet. The astronaut needs to turn around and return to the earth. The process of turning round is what makes the traveller older when he gets back.
    You should really read this, and then ask a more specific question if you are still unclear.
  5. Sep 15, 2014 #4

    Sorry for that!
  6. Sep 15, 2014 #5
    Hi态manimalan 1605. You are right if they do not meet again. One of them at least has to leave his original frame of inertia to see his brother.
    Last edited: Sep 15, 2014
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