Han received his
Ph.D. in
theoretical physics in 1964 from the
University of Rochester. Han's research specialty is in the field of theoretical particle physics, with an emphasis on the symmetry principles of elementary particle physics. Han and
Yoichiro Nambu of the
University of Chicago first introduced a new hidden symmetry among quarks in 1965. This is the origin of the color SU(3) symmetry, distinct from the symmetry among hadrons which is the flavor SU(3). This SU(3) symmetry is the basis for the quantum chromodynamics (
QCD) which is now the standard theory for the strong nuclear force sector of the
Standard Model. Nambu shared 2008
Nobel Prize in Physics for a related work on applying the mechanism of spontaneously broken symmetry, enabling the electroweak sector of the
Standard Model. From 1993 to 1995, Han served as the inaugurating chair of the Outstanding Young Researcher Award (OYRA) Committee of AKPA. He is a recipient of the 1998 Global Korea Award by the Council on Korean Studies of the
Michigan State University. He delivered the keynote address at the 2001 Asian Pacific Heritage Month Celebration at the US-
Environmental Protection Agency in Research Triangle Park, North Carolina in May, 2001. The title of his keynote address was "The New New World." Han is the founding chairman of the Society of Korean-American Scholars (SKAS) and since then, he has served as its editor-in-chief n SKAS. He publishes two alternating weekly electronic newsletters, KASTN and IEKAS, the Korean American Science and Technology News and the Information Exchange for Korean American Scholars. In the fall of 2008, Han left the
University of California at Merced and delivered a special seminar explaining the spontaneously broken symmetry of Y. Nambu that earned Nambu the 2008
Nobel Prize in Physics. Leaving the
Seoul National University in Korea in the fall of 2009, Han delivered a colloquium titled "Nambu and the
Standard Model" and taught a special course titled "Physics for Humanities and Social Sciences Course." In the fall of 2013, Han spent his time at
KAIST (
Korea Advanced Institute of Science and Technology) in Daejeon, South Korea and completed his fifth and sixth books. He also served as an adjunct professor of physics at
KAIST. ==Publications==