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Time Dilation Question - TY

  1. Oct 9, 2008 #1
    I am not a physics major, I just have a lot of time on my hand at work. So I was playing around with the time dilation formula in excel and was plugging different velocity's and different time periods. Here is my question. Say if I was standing in a large room with a particle accelerator and say I was to send a particle around the room for exactly 1 second at a nice and comfortable 99.99% of C. According to the time dilation formula this means that the particle naturally experienced 1 second of motion relative to me, the observer, but I should have experienced 70.712446 seconds. How is this possible if it is happening in front of me. I'm sure I am missing something or did something wrong, maybe even in the formula.

    I appreciate anyone's input.

    Thank You
  2. jcsd
  3. Oct 9, 2008 #2


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    Send it for "exactly 1 second" in whose frame?
    For your math to make sense, you must not have sent it for 1 second of time in your frame, you must have sent it for 1 second of time according to a clock moving along with the particle. From your perspective, that clock is slowed down by a factor of 70.712446, so it will take 70.712446 seconds in your frame to advance forward by 1 second. On the other hand, if you wanted to send the particle out for 1 second of your time, then the particle will only have experienced 1/(70.712446) = 0.014141782 seconds.
  4. Oct 9, 2008 #3


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    Why wouldn't it be possible? The only argument against it that sounds reasonable is the "twin paradox", which is based on a mistake in a calculation. So maybe you should check out the threads about the twin paradox. (There are lots of them. Two of them are still on the first page).

    The key to understanding all problems of this sort is to understand that when you measure a time or a distance, you're measuring the difference between the coordinates of two events (points in spacetime), but another observer wouldn't agree with you about which slice of spacetime is "space". Therefore, when he measures times or distances (e.g. the length of a moving train), he's never comparing the same two events as you are.
  5. Oct 9, 2008 #4
    ok I think I understand now, I think the glass was half full or empty, whichever. But it does make sense.

    Thank You
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