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General relativity question

  1. May 6, 2008 #1
    So is it the closer you are to the centre of a body the slower time will go? or is it the other way round. also why is this?

    my lecturer confused me a bit when explain it, but whats general rel got to do with the orbit of a satellite?
  2. jcsd
  3. May 7, 2008 #2


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    This is a strange question. GR is a theory of gravity, so it is relevant to orbits.
  4. May 7, 2008 #3
    The closer one is to a body of energy (and energy's other forms: heat conduction, pressure, and viscosity), the slower one's rate of time is. It is the gradient of this gravitational time dilation (how much the rate of time slows based on a change in distance) that causes acceleration to occur.

    From a Newtonian point of view (in a weak gravitational field, and where relativistic precession is all but none), the orbiting body maintains a constant rate of time, and so follows a circular path of constant distance from the gravitating body. I believe that this is also referred to as a "straight path in spacetime" results in a "curved path in space".

    As for the actual mechanism behind gravitational time dilation, that's to do with quantum gravity (superstring theory, loop quantum gravity). I cannot go into detail on either, for lack of knowledge.
    Last edited: May 7, 2008
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