I am a Van Vleck visiting assistant professor at the Department of Mathematics, University of Wisconsin-Madison.
I mainly work on probability theory, with focuses on random matrices and free probability.
Contact
Email: hji56 (at) wisc.edu
Postal Address: 480 Lincoln Dr, Madison, WI 53706-1325, United States
Office: Room 522, Van Vleck Hall
Publications and Preprints
Non-Hermitian spectral universality at critical points,
with Giorgio Cipolloni and László Erdős, Probability Theory and Related Fields, 2025, DOI, arXiv:2409.17030
On the spectral edge of non-Hermitian random matrices,
with Andrew Campbell, Giorgio Cipolloni, and László Erdős, to appear in Annals of Probability, arXiv:2404.17512
Spectral Estimators for Structured Generalized Linear Models via Approximate Message Passing ,
with Yihan Zhang, Ramji Venkataramanan, and Marco Mondelli, Proceedings of Machine Learning Research vol 196 (COLT2024), Abstract, arxiv:2308.14507
Density of Brown measure of free circular Brownian motion,
with László Erdős,Documenta Mathematica, 2025, DOI, arxiv:2307.08626
Wegner estimate and upper bound on the eigenvalue condition number of non-Hermitian random matrices,
with László Erdős, Communications on Pure and Applied Mathematics, 2024, DOI, arXiv:2301.04981
Functional CLT for non-Hermitian random matrices,
with László Erdős, Annales de l’Institut Henri Poincaré, Probabilités et Statistiques, 2023, DOI, arXiv:2112.11382
Tracy-Widom limit for free sum of random matrices,
with Jaewhi Park, Annals of Probability, 2025, DOI, arXiv:2110.05147
Local laws for multiplication of random matrices,
with Xiucai Ding, Annals of Applied Probability, 2023, DOI, arXiv:2010.16083
Spiked multiplicative random matrices and principal components,
with Xiucai Ding, Stochastic Processes and Applications, 2023, DOI, arXiv:2302.13502
Regularity properties of free multiplicative convolution on the positive half line,
International Mathematics Research Notices, 2021, DOI, arXiv:1903.02326
Gaussian fluctuations for linear spectral statistics of deformed Wigner matrices,
with Ji Oon Lee , Random Matrices: Theory and Applications, 2020, DOI, arXiv:1712.00931
Education / Work experience
2024 -- : Van Vleck Visiting Assistant Professor, University of Wisconsin-Madison
2021 -- 2024: Postdoctoral Researcher, Erdős group, Institute of Science and Technology Austria
2016 -- 2021: Ph.D. in Mathematical Sciences, KAIST (under the supervison of Prof. Ji Oon Lee)
2012 -- 2016: B.Sc. in Mathematical Sciences, KAIST (Korea Advanced Institute of Science and Technology),