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Gravitation: Loss of Mass

  1. Nov 16, 2004 #1
    Hi everybody,

    Does someone know if mass shrinks while it emits gravitation?

    What I mean is either the gravitation field point of view:
    Does mass need to continuously produce a field of gravitational force and by this lose energy?

    Or the particle view:
    If mass continuously emits gravitons, it must lose energy and thus mass.

    Are these assumptions correct or am I totally wrong?

    Do you know if any observations or experiments indicate this viewpoint?

    I am looking forward to any answer,

  2. jcsd
  3. Nov 16, 2004 #2


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    No mass loss due to gravity. Gravity is not a force like EM. It is more accurate to think of gravity as an allergic reaction by space to the presence of matter [space curves around it]. Assuming their existence, no graviton debt would be incurred. Gravitating bodies would receive just as many gravitons as they send.
  4. Nov 16, 2004 #3
    Thank you for the answer, Chronos.

    But I still would like to know one more thing:

    What about gravitational waves? Though they have not been detected yet, Hulse and Taylor received the physics Nobel Prize for their observation of a double pulsar. The pulsar was discovered in 1974. By theory, it must lose energy in form of gravitation. During the observation, their circulation time decreased as predicted by theory.

    So if no mass is lost, what kind of energy can be lost? Kinetic energy. OK. But what happens if a mass particle "stays still"? Does gravitation stop?
  5. Nov 18, 2004 #4


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    Correct, the orbiting pulsars lose angular momentum, not mass. Which means they spiral in towards each other and will eventually merge. The same thing will happen to the earth. It will spiral into the sun. Fortunately, this will not happen for a very long time.
  6. Nov 18, 2004 #5
    And what happens if mass stays still? Does its gravitational force really stop?
  7. Nov 18, 2004 #6
    String theory explains gravitons as being massless, like a photon,
    and because we don't have the technological know-how we can't detect such a weak unit force.
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