I would like to remember two of my “old friends”, Robert Millikan (1868-died 19 Dec 1953) and Albert Michelson (19 Dec, 1852-1931), who made contributions and an impact in so many different areas of Physics. Commencing with the Millikan oil-drop experiment where the electron charge was measured by suspending it in an electric field such that the forces acting on it were in equilibrium, and thus, by equating the gravitational force with the electric force the electronic charge could be determined. Previously, the ratio of e/m of the electron had been calculated by J.J.Thomson (1856-1940) FRS at Cambridge; hence by calculating e (the electronic charge), Millikan was able to calculate the mass, m of the electron and thus to verify its existence.
Opponents of Albert
Robert was also quite outspoken, claiming that Einstein’s interpretation of the photoelectric effect could not be correct, being convinced of only the wave nature of radiation and not accepting the wave-particle duality. Einstein’s revolutionary idea reignited the corpuscular theory of I. Newton (1643-1727), as such, Millikan was an opponent of Albert. Now enters Einstein and the Michelson-Morley experiment, arguably the most famous null experiment in the history of Physics.
Staying with the most famous null experiments ever, one could argue that Galileo’s null experiment with his cannonballs and the leaning tower of Pisa could run into a close second. Millikan and Morley found that the velocity of the Earth relative to a hypothesized ether was effectively zero. As is known (I assume), the ether was introduced by the Greeks of antiquity, by “Giants” such as Aristotle; however, once science did away with the ether, we had the first experimental verification of Albert’s Special Theory of Relativity. For this experiment, Michelson won the Nobel prize in Physics in 1923.
Shaping the New Physics of the 20th Century
Returning to Robert he was able to calculate another of the fundamental constants of nature, namely Planck’s (1858-1947) constant, h which is pivotal in Quantum Physics. The work of these two was crucial in providing experimental evidence of the “new” Physics that was being introduced into Physics in the 20th century (Relativity and Quantum Mechanics) as well as dismantling the ideas of the Greeks of antiquity which were found to be obsolete. Staying with the Greeks I recall one of my History of Science professors (who will remain nameless) saying to me as young undergraduate of Mathematics and Physics that
“In Aristotle we will probably never find another like him who made so many mistakes”.
Debunking Ancient Greek Ideas
That one sentence has stayed with me throughout my life as I thought it was rather harsh, thus I read Aristotle’s Physics, Aristotle’s four causes and Aristotelian logic (modus ponens etc) which along with Euclid’s elements dominated the western world for almost 2000 years being compulsory reading at Oxford and Cambridge from their inception. I still find that comment extremely harsh.
Returning to Albert and Robert, RIP “old friends”.
