Happy birthday Hans Dehmelt! Born in 1922 in Görlitz, Germany, Dehmelt studied physics at the University of Breslau and served briefly in the Germany army at the end of World War II. After the war, he pursued his career in physics at Duke University and then at the University of Washington, where he remains. Dehmelt pioneered the use of electric and magnetic fields to trap small numbers of particles. In one of his most famous experiments, he trapped a single electron and measured its magnetic moment. For those and other feats, Dehmelt shared the 1989 Nobel physics prize. At the end of his Nobel lecture, he quoted the opening line of William Blake's poem, Auguries of Innocence: "To see a world in a grain of sand" -- and went on to offer his own paraphrase: "To see worlds in an electron."
