Albert Einstein: E=mc2, first printing of his most famous equation

"The mass of a body is a measure of its energy-content"

^{First printing of Albert Einstein's
groundbreaking 1905 paper,}the introduction and derivation of
the most famous equation in modern physics: E=mc²

Albert Einstein: E=mc2

"From this equation it directly follows that:— If a body gives off the energy L in the form of radiation, its mass diminishes by L/c² . The fact that the energy withdrawn from the body becomes energy of radiation evidently makes no difference, so that we are led to the more general conclusion that:

The mass of a body is a measure of its energy-content; if the energy changes by L, the mass changes in the same sense by L/9 × 10²⁰ , the energy being measured in ergs, and the mass in grammes.

It is not impossible that with bodies whose energy-content is variable to a high degree (e.g. with radium salts) the theory may be successfully put to the test.

If the theory corresponds to the facts, radiation conveys inertia between the emitting and absorbing bodies."

-translation from the German by Perrett and Jeffery

EINSTEIN, Albert. Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig? [Does The inertia of a body depend upon its energy-content?] in, Annalen der Physik, Vierte Folge, Volume 18, part 13, pages 639-41. Leipzig, 1905. Octavo, modern half-morocco over marbled boards. $6500.

First printing of one of Einstein's most important papers and one of the most important papers in modern physics.

"A few months after first publishing the theory of relativity, Einstein discovered something that particularly intrigued him; the relation between inertial mass and energy. He wrote to Conrad Habicht during the summer of 1905: 'One more consequence of the paper on electrodynamics has also occurred to me. The principle of relativity, in conjunction with Maxwell's equations, requires that mass be a direct measure of the energy contained in a body; light carries mass with it. A noticeable decrease of mass should occur in the case of radium. The argument is amusing and seductive, but for all I know the Lord might be laughing over it and leading me around by the nose'" (Stachel, Einstein's Miraculous Year). Einstein continued to work late into the summer on this "amusing and seductive" problem before proving the mass-energy relationship that would become known throughout the world as the simple and elegant E=mc². Received by Annalen der Physik on September 27, Einstein's derivation and proof of his most famous equation was a dramatic contribution to his annus mirabilis of 1905. Weil *10. Fine condition. Rare.