Leonid Khachiyan

Leonid Gendrichowitsch Chatschijan (Armenian: Լեոնիդ Գենրիխովիչ Խաչիյան; Russian Леонид Генрихович Хачиян, English: Leonid Khachiyan, May 3, 1952 in Leningrad, † April 29, 2005 in South Brunswick, New Jersey, United States) was a mathematician, the last at the taught Rutgers University in New jersey. His most significant achievement was the development of the first polynomial method for solving linear optimization problems using the ellipsoid method in 1979. Though this method was not suitable for practical use, it provided the basic idea for a lot of randomized algorithms in convex optimization and was thus a significant theoretical result.

Life

Chatschijan was born in Leningrad in a family of Armenian descent, with which he moved at the age of nine years to Moscow. After studying at the Moscow Institute of Physics and Technology of the Russian Academy of Sciences, he received in 1978 and 1984, a PhD in computer oriented mathematics and in computer science. He then spent some years at the same institution as a research assistant in research and teaching. In 1982 he won the prestigious Fulkerson Prize from the Mathematical Programming Society and the American Mathematical Society for major publications in the field of discrete mathematics.

Some years later, in 1989, Khachiyan was a visiting professor at the Institute for Operations Research and Industrial Engineering from Cornell University in New York. A year later he moved to Rutgers University in New Jersey, where he expanded his work on convex optimization problems. In addition, he published together with Bahman Kalantari a series of articles for scaling and balancing of matrices and worked on approximations to multi - commodity flows and on matrix games and decomposition techniques for special convex optimization problems. In 2000, Khachiyan was a U.S. citizen.

In 2005, Leonid Khachiyan, died suddenly of a heart attack. He left behind his wife Olga Pischikova Reynberg and his two daughters Anna and Nina.

In 1983 he was invited speaker at the International Congress of Mathematicians in Warsaw ( Convexity and complexity in polynomial programming ).