““mass and energy have an equivalence. They are two forms of the same thing: energy is liberated matter; matter is energy waiting to happen. Since c2 (the speed of light times itself) is a truly enormous number, what the equation is saying is that there is a huge amount—a really huge amount—of energy bound up in every material thing.4 You may not feel outstandingly robust, but if you are an average-sized adult you will contain within your modest frame no less than 7 × 1018 joules of potential energy—enough to explode with the force of thirty very large hydrogen bombs, assuming you knew how to liberate it and really wished to make a point.””
