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→E=mc2: add Planck
===E=mc<sup>2</sup>===
===E=mc<sup>2</sup>===
Einstein’s famous formula E=mc<sup>2</sup> says that mass and energy can turn into each other. It was first published by H. Poincare. E stands for [[energy]], m is [[mass]], and c is the [[speed of light]]. So, if you increase the energy of a substance, for example by heating it, it gains a minute amount of mass. It was later realized that if you split an atom apart, as in a nuclear explosion, it loses a tiny amount of mass and you release a huge amount of [[energy]].
Einstein’s famous formula E=mc<sup>2</sup> says that mass and energy can turn into each other. It was first published by H. Poincare. Einstein published an alternate derivation that was corrected and improved by M. Planck. E stands for [[energy]], m is [[mass]], and c is the [[speed of light]]. So, if you increase the energy of a substance, for example by heating it, it gains a minute amount of mass. It was later realized that if you split an atom apart, as in a nuclear explosion, it loses a tiny amount of mass and you release a huge amount of [[energy]].
The connection E=mc<sup>2</sup> to nuclear energy is not as direct as pop culture sometimes represents. Einstein did not discover the huge energy available from nuclear reactions. Early workers in radioactivity, such as Ernest Rutherford, understood clearly that the natural radioactive decay of radium released quantities of energy that could not be explained by chemistry, and were much larger than those of chemical reactions. Neither did Einstein originate the key idea that made nuclear energy a possible weapon or a practical energy source. That was Leo Szilard, who acknowledged having been inspired by a 1914 H. G. Wells novel. Szilard discovered or invented the chain reaction (and patented it). What Einstein did was to provide a theoretical framework that accounted for the release of energy, and a quantitative theory that was used by the scientists at Los Alamos who designed and built the bomb.
The connection E=mc<sup>2</sup> to nuclear energy is not as direct as pop culture sometimes represents. Einstein did not discover the huge energy available from nuclear reactions. Early workers in radioactivity, such as Ernest Rutherford, understood clearly that the natural radioactive decay of radium released quantities of energy that could not be explained by chemistry, and were much larger than those of chemical reactions. Neither did Einstein originate the key idea that made nuclear energy a possible weapon or a practical energy source. That was Leo Szilard, who acknowledged having been inspired by a 1914 H. G. Wells novel. Szilard discovered or invented the chain reaction (and patented it). What Einstein did was to provide a theoretical framework that accounted for the release of energy, and a quantitative theory that was used by the scientists at Los Alamos who designed and built the bomb.