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Time and speed of light problem

  1. May 22, 2008 #1
    If you could travel at the speed of light in a rocket ship then you could still walk around in that rocket ship because time is reletive. When you are in your rocketship you would age because time is reletive but you dont age at the speed of light so how is this possible.

    Please correct this because I have to be wrong about something.

    Thank you for helping :smile:
  2. jcsd
  3. May 22, 2008 #2
    Yes, you can walk around.
    An observer moving with respect to you would disagree that you are aging. This is because time is only relative when applied to a different frame of reference.
  4. May 23, 2008 #3
    But if the rocket came to a stop after 50 years of moving at light speed would the guy in the rocket be 50 years older than he was.

    If so then how is it possible that you dont age at the speed of light.
  5. May 23, 2008 #4
    He would not be. Coming to a stop is the problem. As soon as you accelerate, you experience massive gravitational time dilation.
  6. May 23, 2008 #5
    So if you go the speed of light you will not be able to slow down to a stop or slow down at all?
  7. May 23, 2008 #6


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  8. May 23, 2008 #7

    "no information or material object can travel faster than light."

    This a quote from that wiki page.

    It says material things cant go faster than the speed of light but it doesnt say they cant go as fast as the speed of light.

    Photons are material things and they are light (so they are traveling at the speed of light).
  9. May 23, 2008 #8
    Good one buddy!
    However, I think, photons can go at light speed as they are massless. With increase of mass, the speed limit should decrease, due to energy requirements. So any material body can't reach the speed of light, nor can exceed it.
  10. May 23, 2008 #9


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    you'd make a better lawyer than physicist. In spite of what Wiki says I stand by my original post.

    Whoever told you that is wrong. Photons do not have mass.
  11. May 23, 2008 #10

    Doc Al

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    Staff: Mentor

    Your post is entirely consistent with the wiki page (and would be true even if it wasn't!). Here's another quote from that same page:
  12. May 23, 2008 #11
    Ok thanks for answering my question :approve:
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