/sci/ - Science & Math

I don't understand gravity. The popsci explanation is that it's created by the curvature of spacetime and objects aren't actually attracted to one another but are only following that curvature. But that only explains why objects that are already moving fall down. Why would a stationary object follow that curvature and fall? If I drop a pen, where is that force coming from to push it down? Is it because they're moving through time? Please help