Yeah, gravity. Things have a constant acceleration, because gravity pulls them down at that rate. Feathers, don't fall as fast as other objects, because they are pushed against by air pressure. These are my proofs, Newton new this, everybody who has ever been to school has learned this. We have proof, you have nothing. I guess, is not proof.
Really? That's because the bowling ball, doesn't have enough mass to create a strong enough gravitational pull to do something like that. The Earth, is absalutely massive compaired to a bowling ball, and it only pulls objects towards it at 9.8m per second squared.