Hae-Sang Sun

Assistant professor
Department of Mathematics,
Chungbuk National University,
410 Seongbong-ro, Heungdeok-gu, Cheongju,
Chungbuk 361-763, Korea.

Office	40-405 ( Room 405 on the 4th floor of Natural Science Building 40 )
Telephone	+82-43-261-2243 (office)
	+82-10-2607-3151 (cell)
E-mail	haesang [at] chungbuk (dot) ac (dot) kr
	haesang.sun [at] gmail (dot) com

Teaching

Fall 2010

Calculus II
Theory of numbers
Algebraic number theory

Mathematics

Research Interests

I am studying special values of various $L$-functions, in particular, non-vanishing mod $p$ of special $L$-values. It includes $L$-functions with cyclotomic and anti-cyclotomic twists. I developed certain homological methods to consider Dirchlet and elliptic modular $L$-values with cyclotomic twists. Anti-cyclotomic twists is related to Shimura curves associated with indefinite quaternion algebra over rational numbers. It is studied using a geometric methods such as Zariski-density of CM points on Hilbert modular Shimura variety. I am also interested in $\mu$-invariant of $p$-adic $L$-functions, modular symbol, equi-distribution, and algebraic geometry.

Here is my research statement.

Publications

• Homological Interpretation of a Theorem of L. Washington, J. Number Theory 127 (2007), no. 1, 47-63.
• Cuspidal class number of the tower of Modular Curves $X_1(Np^n)$, Math. Ann. 348 (2010), no. 4, 909-927
• Derivative of power series attached to $\Gamma$-transform of $p$-adic measures, J. Number Theory 130 (2010), 10-26
• Borel's conjecture and the transcendence of the Iwasawa power series, Proc. AMS 138(2010) no.6 1955-1963
• Non-vanishing mod $p$ of special $L$-values, Ph.D. Thesis