How General Relativity Produces Gravity

Mass/Energy Curves Space-Time
A massive body such as the Earth creates a significant curvature of space-time. The situation is analogous to setting a bowling ball on a bed; the heavy ball depresses a nearby region of the bed's surface.
mass causes curvature
Figure 1: A Bowling Ball Placed on a Bed
As the ball is lowered, the surface of the bed sinks.

Curvature of Space-Time Leads to Acceleration
When another object moves through space-time, it feels the curvature created by the massive body. A marble thrown onto the bed moves toward the bowling ball. Because its motion is not along a line and its speed changes, the marble is accelerating.
curvature causes acceleration
Figure 2: A Marble Moving on a Bed with the Bowling Ball on It
The marble moves along a curved trajectory and hits the ball.

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