More than any other equation in physics, E = mc² is recognizable and profound. But what do we actually learn about reality from it? ===================================================================== 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 doesn't even describe his most famous equation, which is E = mc². - Public Domain ====================================================================== Key Takeaways: * First introduced way back in 1905, Einstein’s most famous equation, E = mc², put forth the mathematical formula...