Joseph Polchinski

Joseph Polchinski (May 16, 1954 – February 2, 2018) was an American theoretical physicist and string theorist. He was born in White Plains, New York. Polchinski wrote the two-volume textbook "String Theory", published in 1998. Among his many contributions to theoretical physics, D-branes are the best known. In 2008 he won the Dirac Medal for his work in superstring theory. He won the 2017 Fundamental Physics Prize.
Polchinski died on February 2, 2018 in Santa Barbara, California at the age of 63.