1.From the I see gravity is the only force that requires no energy. Because when I fall gravity is pulling me down. This is between the earth and me. Yet neither of us give any energy. I actually lose energy while I accelerate due to air. Yet I still gain energy. Why? Were does this energy comes from. 2.question two is about the graviton. My gravitons move out at the speed of light. And never slow down. Light moves out at the speed of light but slows down in gases, air, and liquids. This is because the photon is basically dodging interactions between the matter? Photons can accelerate and be stopped, gravitons can't be stopped. Same reason as above? Question one is more important!