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Time dilation question

  1. Oct 20, 2008 #1
    Apparently time flows slower in a system thats travelling at roughly the speed of light, but time dilation says that a time interval on earth is longer than in the system travelling at v=c.Shouldn't that lead to the conclusion that time is flowing faster in a v=c system?

    Excuse the lack of detailed description, as English is not my first language.
  2. jcsd
  3. Oct 20, 2008 #2


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    Your English is excellent but it is still not at all clear what you are asking. "time flows slower in a system thats travelling at roughly the speed of light" is incorrect. Time flows slower that's traveling at roughly the speed of light relative to another system.

    If we could observe what is happening in a system traveling at close to the speed of light (nothing would be happening in a system moving at the speed of light!) we would see things happening slower- its time would have slowed down. Conversely, we would be moving close to the speed of light as measured from the other system. They would observe time slowed down in our system.

    I think your problem is with the phrase "time flow". If I observe something happening in another system taking twice as long, I observe time slowed down. The time interval for an action being twice as long does NOT mean that time is "flowing" faster.
  4. Oct 20, 2008 #3
    This complements Halls post: Each moving observer sees the OTHER observer as in motion and hence the OTHER clock as slower; each perceives their OWN clock ticking normally. The point is that time is NOT absolute, motion is not absolute, length (space) is not absolute. All depend on the velocity (and maybe acceleration) of the observer.

    Frames of reference are confusing and even Einstein spent considerable time studying them before launching into special relativity...they take effort,time and patience to understand...I'm still trying to!!!
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