John Bardeen (bɑrˈdiːn; May 23, 1908 – January 30, 1991) was an American physicist and electrical engineer. He is the only person to be awarded the Nobel Prize in Physics twice: first in 1956 with William Shockley and Walter Brattain for the invention of the transistor; and again in 1972 with Leon N. Cooper and John Robert Schrieffer for a fundamental theory of conventional superconductivity known as the BCS theory.
The transistor revolutionized the electronics industry, making possible the development of almost every modern electronic device, from telephones to computers, and ushering in the Information Age. Bardeen's developments in superconductivity—for which he was awarded his second Nobel Prize—are used in nuclear magnetic resonance spectroscopy (NMR), medical magnetic resonance imaging (MRI), and superconducting quantum circuits.
Born and raised in Wisconsin, Bardeen received a Ph.D. in physics from Princeton University. After serving in World War II, h