| Dodece said: Technically speaking the equation is incorrect. We now know that the speed of light isn't constant. Scientists in the laboratory have managed to slow light down considerably, and via quantum tunneling light can move faster then it would typically move. That isn't to say the equation doesn't work. Just that something thought to be a constant is not in fact a constant. |
The speed of light is only considered constant under vacuum, and that is the speed of light used in this equation. The c^2 is only a constant linking the relation of mass and energy, similar to say Hooke's law relating force and displacement with a constant k. So essentially it could have been anything, but it just happens to be the speed of light under vacuum squared. I believe the equation is just meant to show that mass and energy are proportional and can freely convert between each other given the right conditions (like in the seconds after big bang).
Also quantum tunneling is a phenomenon due to Heisenberg's uncertainty principle, I don't think its so much travelling faster than the speed of light but rather the fact that there is always an uncertainty related to the position of a moving particle, so it can sometimes be in places that classical physics would forbid (as classical physics has no uncertainty), which makes it appear as though it is travelling faster than the speed of light. Anyway thats basic quantum physics though, the concepts of it never did make sense to me. Only that it has a much more sound underlying mathematical basis.
