Electrons are quanta of electricity & photons, quanta of light, named by GJ Stoney & by GN Lewis, respectively. Precisely a century ago, "JJ" THOMSON presented results from his cathode ray experiments establishing the reality of this minute electric "corpuscle". Similarly at the very end of that same century, Max PLANCK explained black body radiation data in terms of a new statistical model requiring discrete quanta of energy.
But concepts underlying such discrete electrical & optical quanta had been emergent during most of the 19th Century. In part, these began with Michael FARADAY's electrochemical equivalent [F], Amadeo AVOGADRO's number [N], & Ludwig BOLTZMANN's constant [k], & the ideal gas constant [R]. Thus PLANCK in 1900 could compute the first fairly accurate value of the electron charge as
Also William Rowan HAMILTON's optical-mechanical analogy by 1837 had contained within it the germs of
which were finally revealed only in our own century.
So this lecture explores these & other heroes & highlights of
this 19th Century story, pursuing ultimate consequences of the electron-photon
nexus down to the quantum electrodynamics [QED] of our own time.