Kadel replies: Vladimir Krasnopolsky writes that special relativity has several authors and specifically mentions publications by Hendrik Lorentz that were earlier than Einstein’s 1905 paper. One reader wrote to me indicating the contributions of Henri Poincaré, and interested parties can find a summary of Poincaré contributions, with accompanying references, on Wikipedia (http://en.wikipedia.org/wiki/Henri_Poincar%C3%A9#). Evidently, he promoted Lorentz’s work and, before 1905, promulgated the “principle of relativity” and an early form of E = mc 2 regarding the properties of emitted radiation. Recollecting from my undergraduate education, I believe it is correct to state that Einstein was the first to derive special relativity without reference to electromagnetism and the first to write down what we sometimes call the equivalency of mass and energy, or what I referred to in my previous letter as Einstein’s third law.
An internet search on “Einstein’s laws” returned hundreds of websites that use precisely that terminology when referring to special relativity. Included among them is the “Laws of Science” (http://en.wikipedia.org/wiki/List_of_laws_in_science), which has the energy of photons, special relativity, and general relativity all under Einstein’s name. So it’s hard to be original, and the general public may be ahead of us—or at least me—in this discussion.
I exchanged private e-mails with Helen Quinn shortly after our writings appeared in the same issue of Physics Today. She wrote that her “impression is that the idea of a law became archaic right about the time it was realized that Newton’s laws were not absolutely true in all circumstances. But we never gave up using the term for ideas that had already been blessed with that language usage.” She asked, as does William Hooper, who would decide, and whether some international body of physicists should be empowered to promote theories to laws, just as the International Astronomical Union declared that Pluto is not a planet. I agree with that proposal, but I’ll caution that Pluto is still a planet to me.
Hence, I make my own prejudice clear as to theories versus laws. Unlike Gregory Mead, Joseph Ribaudo, or Lewis Wedgewood, I find the idea of a law much more compelling than a theory. In my own corner of physics—elementary-particle or high-energy physics—we have, for example, string theory and supersymmetry theory. Although both propose solutions to perceived problems with the standard model of high-energy physics, neither has made a prediction that has yet been verified by experiment. (My theoretical colleagues will disagree, and they will happily point out that in supersymmetric theories, in which every quark, lepton, and gauge boson we currently know acquires a new partner, about half of the supersymmetric particles have already been discovered. Some may argue that the observation of “dark matter” is actually the detection of supersymmetric particles, but to me the connection has not yet been made.) Furthermore, in casual conversation, private thinking, or everyday life, one frequently hears—or asks—the question, “Does it violate the laws of physics?” I’ve never heard “Does it violate the theories of physics?” I vote for the laws of special relativity, and in deference to history and the input from readers of my letter, let a duly organized body of physicists assign attribution, lest others do it for us.
