History Of E = MC2

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Trigger

Recently read Was Einstein the First to Invent E = mc2? The great physicist was not the first to equate forms of mass to energy, nor did he definitively prove the relationship

Relevant quotes from above article (emphasis added):

1. “In 1881 J. J. Thomson, later a discoverer of the electron, made the first attempt to demonstrate how this might come about by explicitly calculating the magnetic field generated by a moving charged sphere and showing that the field in turn induced a mass into the sphere itself. ”
2. “... but in 1889 English physicist Oliver Heaviside simplified his work to show that the effective mass should be m = (4⁄3) E / c2, where E is the energy of the sphere’s electric field. German physicists Wilhelm Wien, famous for his investigations into blackbody radiation, and Max Abraham got the same result, which became known as the “electromagnetic mass” of the classical electron (which was nothing more than a tiny, charged sphere). Although electromagnetic mass required that the object be charged and moving, and so clearly does not apply to all matter, it was nonetheless the first serious attempt to connect mass with energy.”
3. “When Englishman John Henry Poynting announced in 1884 a celebrated theorem on the conservation of energy for the electromagnetic field, other scientists quickly attempted to extend conservation laws to mass plus energy. Indeed, in 1900 the ubiquitous Henri Poincaré stated that if one required that the momentum of any particles present in an electromagnetic field plus the momentum of the field itself be conserved together, then Poynting’s theorem predicted that the field acts as a “fictitious fluid” with mass such that E = mc2. Poincaré, however, failed to connect E with the mass of any real body.”
4. “The scope of investigations widened again in 1904 when Fritz Hasenöhrl created a thought experiment involving heat energy in a moving cavity. ... Then one of Austria’s leading physicists, he wrote a prize-winning trilogy of papers, “On the theory of radiation in moving bodies,” the last two of which appeared in the Annalen der Physik in 1904 and early 1905. ... A simple application of the “work–energy theorem,” which equates the difference in work produced by the forces to the cavity’s kinetic energy, allowed Hasenöhrl to conclude that blackbody radiation has mass m = (8⁄3) E / c2. In his second paper Hasenöhrl considered a slowly accelerating cavity already filled with radiation and got the same answer. After a communication from Abraham, however, he uncovered an algebraic error and in his third paper corrected both results to m = (4⁄3) E / c2. ”
5. “One naturally wonders whether Einstein knew of Hasenöhrl’s work. It is difficult to believe that he did not, given that the bulk of the prize-winning trilogy appeared in the most prominent journal of the day.”

Takeaway

Like so many times before and after, an invention or discovery is not the work of a single human being.

As I have argued before on this blog, intellectual property rights urgently need to be reformed or even abolished. As a minimum, the duration of intellectual property rights should be dramatically shortened. Just because someone was the first or fastest to patent something is not justification enough.