There are huge holes in the theory of gravity, the main one is forces going in opposite directions when you "drop" an object ( bouancy ) but also there is no evidence of acceleration when objects supposedly fall. Check an accelerometer on your phone when you drop it. If it is moving downwards, it needs to accelerate.

The fundamental force is the earth moving upwards. The opposite is inertia. Without the motion, we have no up down, sense of direction or weight.