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What causes gravity?

  1. Jul 6, 2011 #1
    The reason why we have gravity.

    I think it is because of the insulation we have between us and the center of the Earth.

    The earth beneath us separates space itself. Space wants to go back to that center point in the Earth, however it can't because the elements in the ground are in the way.

    So, space is always pushing down on us and everything on the surface of Earth, trying to go to that center point.

    Now, let's think in terms of density.

    For instance, what if the Earth was made of aluminum. Aluminum is not a dense material, so it does not insulate space from the center point very well.
    It has too much empty spaces in it's molecules for space itself to occupy. Therefore we would weigh much less on the surface of an aluminum planet. Space can not push back very hard with there being too much space between us and the center point.

    Now, if the Earth was made of a much denser material, like gold, as a good example.

    Gold would be a very good insulation against space. There is much less space between the molecules than aluminum.
    On a planet of solid gold the same size of as our Earth, we would weigh an incredible amount. Space would be pushing us toward the center point extremely hard.

    So, thankfully, we have just the right density of materials, and just enough space under us that gives us a tolerable push toward the center point from the space around us.

    Space appears to be a form of energy.

    Or it could be that the earth under us simply compresses space like a spring, and it pushes back on us.

    I know that this is not the conventional answer, but conventional science only states that gravity exists, yet gives no suitable explaination for it.
    Last edited: Jul 6, 2011
  2. jcsd
  3. Jul 6, 2011 #2
    Mass causes gravity. There is nothing magical about the center of the earth. An object on the surface experiences gravitational attraction to every bit of mass in the earth; the core, the mantel, the mountains to the west, etc; all those forces just add up to give a net force that points towards the center of the earth.

    Words such as "space", "density", and "insulation" have very specific meanings in science, and should be used carefully, otherwise your thoughts come across as nonsense. For instance, space cannot "push" because it is not a force.
  4. Jul 7, 2011 #3
    It certainly is not a conventional answer. The real issue with your suggestion of what gravity is, is that it is so speculative with no explanation for why space wants to get to the center of the earth. Or why space isn't at the center of the earth right now (as most people believe it is). You are attempting to explain gravity, but by your attempt at it you raise more questions than we have right now.

    There is some explanation for gravity in Einstein's theory of general relativity. According to that theory mass/energy warp spacetime, creating an effect that appears to look like gravity. Basically it says that mass/energy tell spacetime how to curve and spacetime tells mass/energy how to move. You might find http://en.wikipedia.org/wiki/Geodesic" [Broken] interesting.
    Last edited by a moderator: May 5, 2017
  5. Jul 7, 2011 #4


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    The explanation of gravity by conventional science is perfectly suitable to me. It sounds like you just don't like/understand it.
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