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Why is gravity so weak?

  1. Jul 9, 2015 #1
    Why am I able to repel two liked poles magnet despite the presence of earth gravity? The earth gravity is able to hold skyscrapers together but yet unable to prevent two magnets from repelling?

    I know there is an explanation that says that unlike graviton, all the other fundamental forces are bound to the brane. Thus gravity is able to propagate into other dimensions resulting in what we experience the weaker gravity force.
    I dont really get this but is there other way to explain?
  2. jcsd
  3. Jul 9, 2015 #2
    There is a very similar current thread that you might want to look at.

    Don't count on brane theory as having anything to with it, or any other theory involving higher dimensions.
    Mathematical models of that sort exist but have not been experimentally verified in any way.

    We don't yet know why the fundamental forces are different in magnitude, it's work in progress.

    Also gravity is not the main force involved in keeping a skyscraper together, electrostatic bonds between atoms do that.
    If you somehow teleport the skyscraper into interstellar space it will not suddenly disintegrate.
    Last edited: Jul 9, 2015
  4. Jul 10, 2015 #3


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    Staff: Mentor

    Best answer from the other thread:
    In other words, in a universe full of only protons, or with stars made of protons and planets made of electrons, electromagnetism would dominate. But since the universe has a near equal number of protons and electons, those forces cancel out over very short distances whereas gravity always adds.
  5. Jul 10, 2015 #4


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    Staff: Mentor

    A number of off topic posts and replies to these posts have been deleted. I remind all members to please stay on topic.
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