John Bardeen (1908-1991), American physicist and Nobel laureate, born in Madison, Wisconsin, and educated at the University of Wisconsin and Princeton University. As a research physicist (1945-1951) at the Bell Telephone Laboratories in Murray Hill, New Jersey, he was a member of the team that developed the transistor, a tiny electronic device capable of performing most of the functions of the vacuum tube. For this work, he shared the 1956 Nobel Prize in physics with two colleagues, the American physicists William Shockley and Walter H. Brattain. Meanwhile he had joined (1951) the faculty of the University of Illinois. In 1972 he shared the Nobel Prize in physics with the American physicists Leon N. Cooper and John R. Schrieffer for the development of a theory to explain superconductivity, the disappearance of electrical resistance in certain metals and alloys at temperatures near absolute zero (see Cryogenics). Bardeen thus became the first scientist to win two Nobel Prizes in the same category.