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Homework Help: My gravitons move out at the speed of light

  1. Jun 29, 2006 #1
    1.From the I see gravity is the only force that requires no energy.
    Because when I fall gravity is pulling me down. This is between the earth and me. Yet neither of us give any energy. I actually lose energy while I accelerate due to air. Yet I still gain energy. Why?

    Were does this energy comes from.

    2.question two is about the graviton.
    My gravitons move out at the speed of light. And never slow down.
    Light moves out at the speed of light but slows down in gases, air, and liquids. This is because the photon is basically dodging interactions between the matter?

    Photons can accelerate and be stopped,
    gravitons can't be stopped. Same reason as above?

    Question one is more important!
  2. jcsd
  3. Jun 29, 2006 #2
    You gain kinetic energy as you fall and you lose potential energy (taking the surface is the datum). If the field is conservative, the total energy of the (earth + you) system is constant.
  4. Jun 30, 2006 #3
    Oh, forgot about that...(:D)
  5. Jun 30, 2006 #4
    and remeber that potential energy is realtive Ek = mgh but you can change h to be whatever you like it to be
  6. Jul 2, 2006 #5


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    Homework Helper

    Other Forces do NOT require Energy, either, until there's motion.

    photons go slow in matter because they DO interact (push and pull matter)
    they don't "dodge" around the atoms.
    [a typical photon is a thousand times larger than an atom.]

    gravitons stop when they're absorbed ... same as photons.

    [one way to treat light speed in material is absorbtion and delayed re-emission. don't expect a graviton theory to treat this until
    it is unified with General Relativity.]
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