Edward Teller was a Hungarian-born American theoretical physicist who, although he claimed he did not care for the title, is known colloquially as "the father of the hydrogen bomb". He made numerous contributions to nuclear and molecular physics, spectroscopy and surface physics. His extension of Enrico Fermi's theory of beta decay, in the form of the so-called Gamowâ€“Teller transitions, provided an important stepping stone in its application, while the Jahnâ€“Teller effect and the Brunauerâ€“Emmettâ€“Teller theory have retained their original formulation and are still mainstays in physics and chemistry. Teller also made contributions to Thomasâ€“Fermi theory, the precursor of density functional theory, a standard modern tool in the quantum mechanical treatment of complex molecules. In 1953, along with Nicholas Metropolis and Marshall Rosenbluth, Teller co-authored a paper which is a standard starting point for the applications of the Monte Carlo method to statistical mechanics.
Teller emigrated to the United States in the 1930s, and was an early member of the Manhattan Project charged with developing the first atomic bombs. During this time he made a serious push to develop the first fusion-based weapons as well, but these were deferred until after World War II. After his controversial testimony in the security clearance hearing of his former Los Alamos colleague J. Robert Oppenheimer, Teller was ostracized by much of the scientific community. He continued to find support from the U.S. government and military research establishment, particularly for his advocacy for nuclear energy development, a strong nuclear arsenal, and a vigorous nuclear testing program. He was a co-founder of Lawrence Livermore National Laboratory, and was both its director and associate director for many years.