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Gravity waves and particles

  1. Jun 17, 2014 #1
    when anything moves it displaces space and generates gravity waves, So does this also happen at the quantum level? quarks giggering about due to uncertanty in there possition (at least I think that what uncertanty does acording to explanations in popular science books.) gluons zapping about keeping nucleons together. does this activity generate ripples in spacetime?
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  3. Jun 17, 2014 #2


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    That depends on how it moves. A massive object sailing by at constant speed does not generate gravitational waves, for example.

    It happens at the quantum level, but not for the examples you give, which are stationary states. Uncertainty in position means just that, it does not mean the particle is jiggering about! Yes, the electrons in an atom do not have a well-defined position, but that does not mean they move back and forth in orbits. And just as they do not generate electromagnetic radiation, they do not generate gravitational waves either.
  4. Jun 17, 2014 #3
    so how would particles generate waves in spacetime at the quantum level?
  5. Jun 17, 2014 #4


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    I hope you understand that, due to the incredible weakness of the gravitational interaction, these examples are hypothetical. They've never been observed, and probably never will be, but in principle they are possible.

    a) Any particle reaction may, in addition to the other products, emit a graviton.
    Such as, p + p → p + p + g or n → p + e + ¯ν + g

    b) A nuclear transition. Just as a nucleus may emit a gamma ray, subject to certain selection rules on ΔL and ΔP, it could, in principle, emit a graviton. A photon carries spin 1 with odd parity, while a graviton is spin 2 with even parity, so the selection rules are not the same.
  6. Jun 17, 2014 #5
    Slightly off-topic: It is interesting isn't it? It does seem wrong to say the electrons in orbits are moving about, yet, one *can* compute probability currents, and vorticities and orbital angular momentum and so on, which certainly make it *seem* like some sort of funny motion is occurring. I don't know that I am totally convinced that simply because a state is in a time-independent state that no motion is occurring in it. Ignoring the small scale details, a stationary wave in a river is time independent, as is say a sphere rotating on some axis.

    Of course, a charged rotating sphere doesn't emit either electromagnetic radiation nor gravitational waves, despite that we agree it is "moving".
  7. Jun 17, 2014 #6
    well where i am going with this is. could gravity be caused by quantum level viberations in spacetime that arise from the activity of particles. for instance, say you have a beem of light traveling through space, the light causes spacetime to viberate like a bow drawn across a violin string. these waves carry gravitons. the gravatons are phonons...just a wild thought.
  8. Jun 17, 2014 #7


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    Thread is closed due to violation of PF Rules.

    Last edited: Jun 18, 2014
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