My academic training started in Iwasawa theory. It focused on analytic aspects of p-adic L-functions, with an eye toward phenomena over nonabelian p-adic Lie extensions of number fields. Then my interest shifted to Diophantine problems, on both the computational and the theoretical sides. Almost simultaneously, I worked on arithmetic quantum field theory, a relatively new field that studies action functionals arising from number theory. Two primary examples are arithmetic Chern–Simons, or Dijkgraaf–Witten, theory and arithmetic BF-theory. The involvement with arithmetic field theory motivated me to embark on a study of the Rédei symbol and its generalizations. Meanwhile, I had an opportunity to learn how ergodic theory applies to arithmetic through a case study of certain Bianchi manifolds, in the hope of saying something about L-values of Bianchi modular forms. This is a long way from p-adic L-functions to Bianchi L-functions. I have also worked on several miscellaneous projects: derived Hecke operators, Dwork's approach to rationality of zeta functions, reduction of some algebraic surfaces, the Bertrand–Rodriguez Villegas conjecture, Euler–Kronecker constants, Ennola's conjecture, and monogenicity of number fields. All of these are great fun, but I find L-functions the most mysterious among them.
I have been fortunate to collaborate with Magnus Carlson, Jinwoo Choi, Hee-Joong Chung, John Coates, Kwon Hong, Minchan Kang, Minhyong Kim, Jaesung Kwon, Jungwon Lee, Seonhee Lim, Masanori Morishita, Georgios Pappas, Jeehoon Park, Junyeong Park, Seungho Song, Ingyu Yang, and Hwajong Yoo.
Last modified: October 28, 2026