stop using "gravity" like a verb gravity is not the thing doing the doing. gravity is just what we call the observation of it happening. think of like this. a jet flies over your head and it breaks the sound barrier you see it go by and shortly after you hear a sonic boom the sonic boom is just the name we give the phenomenon you would never say "i dont believe in sonic boom" or you would not say "show me how that works without sonic boom alone" see how nouns don't wok in that sentence? it's because you are applying gravity to mean something it isn't gravity is just the sonic boom of the ball coming back down again.