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Speed of light vs speed of time

  1. Dec 27, 2009 #1
    i submit a question to the physics community.

    take the whole twin paradox into account. ok.

    now time is relative to speed, and also gravity, yeah.

    now in physics we measure the speed of light as a constant though for time it is variable (ultimately due to the effect on us)

    electromagnetic waves(which light is also a variance of) have been measured to travel slower passed an object with a large gravitational field.

    now if someone is travelling further away from the solar system, invariably getting further away from close proximity of gravitational masses) would he not start travelling a faster measured length of speed while maintaining the time dialation he has created due to accelerating ???
  2. jcsd
  3. Dec 27, 2009 #2
    so my question is y have the speed of light as a constant if it does change while having the same amount of time dialation(e.g infinite for electromagnetism)
  4. Dec 27, 2009 #3
    i mmean electromagnetic waves not electromagnetism, i'm on holiday
  5. Dec 28, 2009 #4


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    Homework Helper

    umm.... I'm really not sure what you're getting at. But the speed of light (in vacuum) is a constant, 299792458 m/s.
  6. Dec 28, 2009 #5


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    I can sort of see what you're trying to ask, but this statement

    "now time is relative to speed, and also gravity," is not a good way to say that clocks that are in different gravitational environments, or moving relative to one and other, will show different elapsed times when compared at one place.

    Think of the universe as a collection of observers with clocks. Some are on rocks like us, some are in spaceships and so on. If they each do an experiment using their clocks and rulers to measure the speed of light, they will all get the same number ( after converting to a common unit base ). It would not matter if the light used in the experiment came from a local laser or through the lab window from a distant or close star or planet or whatever.
  7. Dec 28, 2009 #6
    i just reckon that it all hasn't been examined using more information that was available than at the time it was theorised. i mean it works reeally well i just believe that there is more to it
  8. Dec 29, 2009 #7
    does anyone reputable have any comments ?
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