http://einstein.stanford.edu/...
Frame Dragging
The purpose of this activity is to demonstrate how the Earth twists the local spacetime frame, but does not affect a distant spacetime frame. The ball represents the Earth, the honey represents spacetime, and the peppercorns represent other masses (stars, planets, etc.) in the spacetime frame at various distances. The food coloring is used to highlight the honey's motion, and does not represent an astronomical object.
A major limitation of this model is that the Earth spins much faster than you can twist the ball (~1,000 mph), and the spacetime frame spins much, much slower (~10 -9 mph) relative to the Earth's rotation than the honey moves relative to the ball's rotation.
The rotation of the Earth does twist the spacetime frame like the ball twists the honey, although it is not caused by "friction" between the Earth and local spacetime. It is unclear to scientists exactly how this phenomena occurs. The theory of general relativity suggests that spacetime and masses have a mysterious mutual "grip" on each other.
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