Part of the show Naked Science Q&A and the Science of Happiness
Nelson in Norfolk asked:
Do you think we'll ever beat the speed of light?
As far as we know, we probably can't. With everything we currently know, the closer you get to the speed of light, the more energy you need to go a little bit faster and you'd need an infinite amount of energy to go at the speed of light. But that isn't to say that something might not change as we learn more and more. The amount of kinetic energy something has normally equals m (mass) multiplied by v (velocity) squared. As you get faster and faster, there's another component going in which is inversely proportional to the speed minus the speed of light. So as you get closer to the speed of light it gets closer to infinity. So as you get faster you notionally get bigger so you need more energy to speed you up. As you get faster and faster, that tends towards infinity. As far as we know, there's no way to bypass that unless the world doesn't work quite the way we think.