Why, in general relativity, does the distortion of the spacetime cause a body initially at rest near a gravitational field to start moving? The usual answer is that the body follows the curvature of spacetime, but why does the stationary body start moving? The analogous doubt is imagining a train stationary on curved tracks (a metaphor for two-dimensional curved space) beginning to move just because it is on a curve.
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You'll find that gravity works much like a low pressure system. This is shown clearly in the concept of hydrostatic equilibrium that determines the size of a star. High pressure caused by the heat of the burning gases causes the star to expand without limit. But opposite low pressure from gravity causes the star to shrink. So the star reaches equilibrium at a particular size.
Likewise, you can hold a cork underwater. Why does the cork rise as soon as you let go? The answer is because the pressure of the water under the cork is greater than the pressure of water above. So with the buoyancy of the cork, it rises. If you look at a bubble of air inside a blob of water on the international space station, the bubble stays stationary in the middle of the water because the pressure is equal all around.
So the reason why your stationary object falls is because in the low pressure system of gravity, the pressure below the object is lower than the pressure above the object.
This "low pressure" of which I speak is most likely the reduced pressure of time dilation. Nobel Lauriat Kip Thorne referred to Einsteins Law of Time Warps when he said "Things like to live where they age the most slowly. Gravity pulls them there. And so as an application, the Earth's mass warps time according to Einstein. It slows time near the surface of the Earth. And this time warp is what produces gravity."
foolishmuse
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