Education
He studied physics and mathematical physics at Yonsei University, and earned his Doctor of Philosophy in mathematics at Rutgers University.
He studied physics and mathematical physics at Yonsei University, and earned his Doctor of Philosophy in mathematics at Rutgers University.
He was a researcher at American Telephone & Telegraph Company Bell Labs, Microsoft Research, and was Underwood Chair Professor of Mathematics at Yonsei University. He is currently a Professor of School of Computational Sciences at of Korea Institute for Advanced Study. His main research fields are combinatorics and computational mathematics.
His best known contribution to the field is his proof that the Ramsey number R(3,t) has asymptotic order of magnitude t2/log t.
In 2008 he became director of the National Institute for Mathematical Sciences of South of Korea, but he was discharged in 2011 after being accused of having allegedly misappropriated research funds. However he was found not guilty by prosecution"s investigation.