In the geocentric model, does gravity increase as you travel toward the center of the Earth?
A viewer asks whether, in the geocentric model, journeying to the center of the Earth would mean gravity increases, and whether there is any empirical data.
Answer
No, gravity decreases as you go toward the center. If gravity is caused by matter, which we grant to Newton and Einstein, then wherever there is matter there is gravity, and wherever there is more matter there is more gravity. The further you go into the center of the Earth, the less matter there is beneath you, so the less gravity there is, until at the exact center there is no gravity at all. That center is hard to describe, because matter cannot be divided indefinitely, so you would have something like a Planck-particle center with no gravity, and only once you get outside it do you have gravity, increasing with the mass between the center and the surface. That is why Jupiter, with far more mass between its center and surface, has much more surface gravity than the Earth. Above the surface it reverses: the further you get from the surface, the more the gravity decreases by the inverse square law, until it becomes so small it is barely pulling, which is why weather satellites at about 22,000 miles and the Moon at 240,000 miles still feel some pull but are far out where it is minimal.