Physics 05 - Louis De Broglie

Does his first name strike you somewhere? Yes! He was a descendant of the French Royal Family. Einstein was convinced that light should be regarded not only as a wave but also as a particle. de Broglie argued, if a wave can behave like a particle, shouldn't a particle behave like a wave too? Einstein's wave-particle dualism is an absolutely general phenomenon extending to everything of physical nature. Thus, motion of all particles must be associated with propagation of a wave. Using Einstein's law of photoelectric effect de Broglie derived a simple equation for the wavelength of an electron or any other particle. It was so tiny a wavelength that it was relevant only to subatomic particles. A copy of this thesis reached Einstein through his friend Paul Langevin, who was de Broglie's adviser. Einstein accepted the theory without reservation and praised the work effusively. This doctoral dissertation of de Broglie of 1924 transformed the field of physics.