Tomorrow would have been the 97th birthday of Werner Heisenberg, a German physicist who founded the field of quantum mechanics. In 1925, Heisenberg came up with the first precise mathematical description of the workings of the atom. Two years later, he made his best-known discovery when he found that it was impossible to precisely determine both the position and the momentum of a particle--now known as the Heisenberg Uncertainty Principle. He was awarded the Nobel Prize for physics in 1932 and died in 1976.
[Source: Roy Porter, Ed. The Biographical Dictionary of Scientists, Second Edition. Oxford University Press. 1994.]