Prinz Louis de Broglie 1864
The Wave Surfers 4
Einstein's special theory of relativity states that electromagnetic waves behave like matter under certain circumstances. Furthermore, the famous equation E = mc2 suggested in fact that energy (waves) and matter (particles) are equivalent. De Broglie, a prince from old French aristocracy, took Einstein's equation literally and showed that electrons, meaning particles of matter, behave reciprocally also like waves, a conclusion that no one had drawn yet. This wave–particle-dualism, proven two years later, became a main support of the quantum theory.