"Gravity is one variable in a lot of scientific processes. If you can remove gravity or minimize its effect, then you can understand the other processes that are going on."

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Bodies like the earth are not made to move on curved orbits by a force called gravity; instead, they follow the nearest thing to a straight path in a curved space, which is called a geodesic. A geodesic is the shortest (or longest) path between two nearby points.

— Stephen Hawking