John Bardeen
![](/Images/godic/202412/23/Bardeen3339.jpg")
![John Bardeen, William Shockley and Walter Brattain at Bell Labs, 1948.](/Images/godic/202412/23/Bardeen_Shockley_Brattain_19483339.JPG")
![A stylized replica of the first transistor invented at Bell Labs on December 23, 1947](/Images/godic/202412/23/Replica-of-first-transistor3340.jpg")
![A commemorative plaque remembering John Bardeen and the theory of superconductivity, at the University of Illinois at Urbana-Champaign.](/Images/godic/202412/23/Bardeen_plaque_uiuc3340.jpg")
John Bardeen (May 23, 1908 – January 30, 1991) was an American physicist and electrical engineer, the only person to have won 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.