Einstein and the Relativity Revolution

In 1905, while working as a patent clerk in Bern because he could not find an academic post, Albert Einstein published four papers in the journal Annalen der Physik that transformed physics, a period now remembered as his "annus mirabilis." One paper explained Brownian motion as the visible result of molecules colliding with pollen grains, offering strong evidence that atoms were real; another explained the photoelectric effect; a third introduced special relativity; and a fourth derived the equivalence of mass and energy.