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Effect of Gravity get bent like light around another gravitational source

  1. Sep 1, 2011 #1
    Does the effect of Gravity get bent like light around another gravitational source? If the object is close enough to the Earth does the Earth's gravitational force bent the Moon's or even the Sun's gravitational effect on that object before that "line of sight" event occurs. As Einstein's General Relativity was proven in 1919 with an solar eclipse of the Sun, light bents with a gravitational source why can't gravity.

    Will a Satellite around Earth in Low Earth Orbit feel the Gravitational pull before passing from the protection of the Earth's Umbria or will it feel nothing until the Sun is directly in front of it? If so is there any mathematical evaluation of this occurrance?
  2. jcsd
  3. Sep 1, 2011 #2


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    Perturbations in the gravitational field obey the wave equation, whose characteristics are null surfaces and whose bicharacteristics are null geodesics. High-frequency gravitational waves follow null geodesics just the same as electromagnetic waves do.
  4. Sep 1, 2011 #3


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    Light waves and high enough frequency gravity waves should ollow null geodesics.

    Electric field lines and gravitational field lines (to the extent they exist, but I think they should work for static gravity) are best approximated as following space-like geodesics and not null geodesics.

    Thus the force attracting the Earth to the sun is a central force, not a "lagged" central force. This is important for momentum conservation.

    It's not quite clear if I've interpreted the OP's question correctly - I'm assuming he's thinking of "the effect of gravity" by what I call a "field line", a concept I've actually borrowed from electromagnetism.
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