Hello, back again. I have another question that I have been pondering about. The question I don't get is: light has mass yeah?? even if it's a really small amount. But then how does light go as fast as the speed of light?? Because you would need infinite energy to get at that speed, carrying that mass a long time/distance at that speed surely must use a lot of energy. But then I thought if E=mc2 then entergy is mass x speed of light2 so doesn't that mean, that if it's traveling at the speed of light, it creates it's own energy? That's the only explanation I could come up with. What flaws do I have, as I'm sure I've got some. Thanks Jack.