I really have no business answering this, but in the spirit of Cunningham's law I'm going to try to give an answer how I think of it. Would like some feedback a

I really have no business answering this, but in the spirit of Cunningham's law I'm going to try to give an answer how I think of it. Would like some feedback and some guidance. This is purely a intuitive answer and not at all an academic one. As we know from relativity and time dilation, as our GPS satellites need to be resynchronized as they move fast and at a lesser mass level. The center of the Earth is very heavy and is therefore going through time slower than the rock or surface objects. Gravity doesn't really exist. Gravity is merely the side-effect of heavy-mass objects going through time slower than lighter objects. This is what is meant when it is said that spacetime is curved. So back to your question, where does the extra energy come from to accelerate the rock towards the Earth? An easy way to think of it, expanding on E=mc^2, Et=mc^2, where t is time. As the ball is now falling further and further into the Earth's gravity well, it is now going through time slower and slower. With t going slower, E must increase to balance the equation, which speeds it up.