Ludvig Dmitrievich Faddeev was born on March 23, 1934 and died on February 26, 2017.
He was a Soviet and Russian theoretical physicist and mathematician.
Faddeev was also known for the discovery of the Faddeev equations in the theory of the quantum mechanical three-body problem and for the development of path integral methods in the quantization of non-abelian gauge field theories, including the introduction (with Victor Popov) of Faddeev–Popov ghosts.
Faddeev headed the Leningrad School, in which he along with many of his students developed the quantum inverse scattering method for studying quantum integrable systems in one space and one time dimension.
His extended work led to the invention of quantum groups by Drinfeld and Jimbo.
Ludvig Faddeev passed away at 82 years old.