Edward Teller (; January 15, 1908 – September 9, 2003) was a Hungarian-born American theoretical physicist who is known colloquially as "the father of the hydrogen bomb", although he claimed he did not care for the title. He made numerous contributions to nuclear and molecular physics, spectroscopy (in particular, the Jahn–Teller and Renner–Teller effects) and surface physics. His extension of Enrico Fermi's theory of beta decay, in the form of the so-called Gamow–Teller transitions, provided an important stepping stone in its application, while the Jahn–Teller effect and the Brunauer–Emmett–Teller (BET) theory have retained their original formulation and are still mainstays in physics and chemistry. Teller also made contributions to Thomas–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.