Nathan "Nati" Seiberg (/ˈsaɪbɜːrɡ/; born September 22, 1956) is an Israeli American theoretical physicist who works on quantum field theory and string theory.

He is currently a professor at the Institute for Advanced Study in Princeton, New Jersey, United States.

He was recipient of a 1996 MacArthur Fellowship[1] and the Dannie Heineman Prize for Mathematical Physics in 1998.

[2] In July 2012, he was an inaugural awardee of the Breakthrough Prize in Fundamental Physics, the creation of physicist and internet entrepreneur, Yuri Milner.

[3] In 2016, he was awarded the Dirac Medal of the ICTP.