Hi, Sorry to bring this up again but I have a new question. I understand the e=mc part, you've only got to look at a nuclear explosion, but I don't really get the 'squared'. Given that a nuclear explosion is literally a 3 dimensional shape (let's leave exploring possible hidden dimensions for now), shouldn't it be e=mc^3? Or am I just looking at it too literally? If someone could just lay out the maths as to why this isn't the case...should be able to get my head around it.