Thanks for your answer TT. I read the thread suggested but now my brain hurts! I am a novice that did not do physics at school but am now fascinated by the subject. I saw this somewhere where a question was asked about the energy in a kg of matter (rest)
This is determined by Einstein's...
In e=Mc2 Does c have to be exactly the speed of light? Can it not be a slightly bigger or smaller number? Or does C squared simply represent an enormous number?