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Light Carries Time

  1. Oct 16, 2003 #1

    Light and time are interrelated in a very important manner. Light carries time, i.e. time travels with the speed of light throughout the universe.
    Only in a black hole, time passes infinitely slow because c in a black hole =0.
    Time can be made to pass slowly or faster by making light go slowly or faster.
    Let me take up an example:
    A car is speeding at a speed of 100 m/sec. You will say that the speed of light coming out through the headlights of the car will not be increased by 100. But I believe that this is wrong.
    Let us talk about a spaceship travelling at a speed close to the speed of light say 200000000m/sec. You will see that time actually slows down for the ship. Now, this is proved to be happening.
    But this does not happen just because of the speed of the spaceship. This is because of the fact that speed of light with respect to the ship has decreased. As the speed of light has decreased, the rate of passing of time has also decreased.

    This clearly shows that nature compensates time for speed. If you cant increase your speed beyond a certain limit. then it compensated by decreasing the rate of passage of time.

    This reflects that speed of light is not actually a constant but at the same time it is not possible for any material body to reach the speed of light because then the time would actually stop passing for this object.
  2. jcsd
  3. Oct 17, 2003 #2
    You have it wrong, light doesn't affect 'the speed' of time, the speed of an object affects the shape of space and 'the speed' of time so that the speed of light always looks the same to any observer. Though it should be noted that 'the speed' of time is meaningless, time alays flows at 1 second/second, it is only apparent when comparing spacetimes that are warped in different ways and/or to different degrees.
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