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B Is it possible to stop the graviton?

  1. Nov 23, 2018 #1
    Is it possible to stop the graviton? If it is then anti-gravity is possible.
     
  2. jcsd
  3. Nov 23, 2018 #2

    Paul Colby

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    Gravitons are still speculation. Gravitational waves have been shown to exist and are known to interact with matter. It's hard, perhaps even inconsistent, for a theory containing gravitons not to include absorption (aka stopping) and emission of gravitons. The simple answer to the anti-gravity question is I doubt it. I hold this opinion because the most naive "theory" of gravitons doesn't include repulsive forces. The "theory" is in quotes because it's broken in ways I'm not likely to be able to explain very well.
     
  4. Nov 23, 2018 #3

    mfb

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    Assuming they exist: No.

    And even if you could, this would not be "anti-gravity". We can stop light in matter, is this "anti-electromagnetism"?
     
  5. Nov 24, 2018 #4
    So basically the gravitational force does not exist due to gravitons but something else?
     
  6. Nov 24, 2018 #5
    Would there be a way of stopping the force instead?
     
  7. Nov 24, 2018 #6

    DaveC426913

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    No. This does not follow.

    Not that we know of.
     
  8. Nov 25, 2018 #7
    The theory of the graviton doesn’t include repulsive forces, but you don’t need repulsive forces, all you need is something to block it.
     
  9. Nov 25, 2018 #8
    There methods of stopping electromagnetic waves, so mightn’t there be a way of stopping gravitational waves?
     
  10. Nov 25, 2018 #9

    CWatters

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    It's not a question that can be answered in any meaningful way at the moment.

    Can aliens eat cheese?
     
  11. Nov 25, 2018 #10

    mfb

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    Stopping light is not the same as blocking the electromagnetic interaction either (you can't do the latter). What you can do is stop radiation with very specific frequencies.
    They are completely different things.
     
  12. Nov 25, 2018 #11

    DarMM

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    Gravitation might not involve gravitons, we currently don't know.
     
  13. Nov 25, 2018 #12

    DaveC426913

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    If I understand correctly, gravitons are really the placeholder for the thing that allows gravity to be quantized, and thus reconciled with the quantum mechanical model.

    Though I suppose your statement can still hold true if a new theory arose that replaced QM.
     
  14. Nov 25, 2018 #13

    phinds

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    The current (incomplete) theory governing gravity is General Relatively and in GR, gravity is NOT a "force", it is the geometry of space-time. I don't think you can stop geometry (but it's also true that the REASON GR is incomplete is that it doesn't work well at the quantum level, so that argument may not be valid)
     
  15. Nov 25, 2018 #14

    DaveC426913

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    Not sure what that would look like, even in principle.
    A 2D "funnel" projection of space time would have ... columns with flat tops sticking out of the curved funnel surface - like a protruding volcanic plug from a landscape?
     
  16. Nov 26, 2018 #15
    Assuming that gravitons exist, and assuming it was possible and you had to come up with a way to stop them, how would you?
    I don’t know much about physics, but I’m assuming the reason gravitons ( given they exist) are able to pass through matter because atoms consist of mostly empty space. What if there was a way to reduce the amount of empty space?
     
  17. Nov 26, 2018 #16

    phinds

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    That question amounts to asking "If the laws of physics did not work the way we understand them to work, what would those laws say about <insert nonsense of your choice>"

    EDIT: if you can cite a peer-reviewed paper on how the empty space in atoms could be reduced, then that would be a different story. That is, you can't (here on PF anyway) just hypothesize some weird scenario without explaining the specific mechanism to reach its conditions.
     
    Last edited: Nov 26, 2018
  18. Nov 26, 2018 #17
    What if there was a way to neutralise the nucleus of an atom, what if you came up with an element that had 1 proton and 7 neutrons, the neutrons would act as a blockade and potentially reduce the effect of the positive charge of the proton.
     
  19. Nov 26, 2018 #18

    phinds

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    if you can cite a peer-reviewed paper on how that would be done, then we can discuss it. AGAIN, you can't just make stuff up. This is not a "what if" kind of forum. If you are going to keep throwing out wild speculation, this thread will get shut down.
     
  20. Nov 26, 2018 #19

    berkeman

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    Thread closed for Moderation...
     
  21. Nov 26, 2018 #20

    PeterDonis

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    The thread has become personal speculation, which is off limits here. Thread will remain closed.
     
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