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Mass and Curved Space Question

  1. May 21, 2004 #1
    According to General Relativity, the presence of mass curves space, and this curvature causes the effects of "gravity". Do Einstein's equations give us a clue as to the mechanism by which mass is able to do this? In other words, how does mass curve space? How does it "know" to curve space? And why is it that more mass results in more curvature?

    The source of these questions comes from a reflection upon the old Newton's Law of Gravity. Newton's Law of Gravity provided a very accurate quantitative description of gravity, but did nothing to account for the cause of gravity (aside from the construct of the "field" later on). General Relativity is supposed to clear this up by suggesting that gravity is caused by curved space due to the presence of mass. This doesn't seem to be a complete answer though.
  2. jcsd
  3. May 21, 2004 #2
    The question is only raised when matter is viewed as point particles. For then we wonder what properties are there in a point that can possibly curve space. However, if matter is an extended object, a submanifold of space-time, then we can easily invision curvatures on the submanifold of matter giving rise to curvatures in space-time that surrounds it. In other words, matter particles themselves are regions where curved space is conserved through time, and the curved space-time of gravitation is where space-time gradually changes in a continuous manner to match the flatness of empty space.
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