This 1934 photograph shows Einstein in front of a blackboard, deriving Special Relativity for a group of students and onlookers. Although Special Relativity is now taken for granted, it was revolutionary when Einstein first put it forth, and it isn’t his most famous equation; E = mc² is. (Credit: public domain)

The true meaning of Einstein’s most famous equation: E=mc²

More than any other of Einstein’s equations, E = mc² is the one that most people can name. But what does it all mean?

For hundreds of years, there was an immutable law of physics that was never challenged: that in any reaction occurring in the Universe, mass was conserved. That no matter…