Edward Teller (Hungarian: Teller Ede; January 15, 1908 – September 9, 2003) was a Hungarian-American theoretical physicist who is known colloquially as "the father of the hydrogen bomb" (see the Teller–Ulam design), although he did not care for the title, and was only part of a team who developed the technology. Throughout his life, Teller was known both for his scientific ability and for his difficult interpersonal relations and volatile personality.