At the Big Island, Hawaii, by Hongjie Zeng.
I am Yusen Xia (in Chinese: 夏雨森, which reads "hsia yü sen "). I’m a 5th year PhD student at Mathematics Department, UC Santa Barbara (fortunately advised by Prof Guofang Wei).
I will be on the job market looking for Postdoc positions in Fall 2026.
I got my BSc in Mathematics degree (with First Class honors) from Hong Kong University of Science & Technology (HKUST). I was an exchange student at UCLA from Winter to Spring 2020.
My CV is here.
I am currently insterested in geometric analysis, in particular eigenvalue problems of Laplace operator on manifolds.
Email: yusen (AT) ucsb (DOT) edu
Department of Mathematics, University of California, Santa Barbara
552 University Rd, South Hall, Santa Barbara, CA 93106
A Sharp Diameter-Dependent Lower Bound for the First Nonzero Neumann Eigenvalue of Geodesic Triangles in Space Forms, with Shoo Seto & Guofang Wei, Preprint, arXiv:2608.16136 (2026)
On the PPW Conjecture for Hopf-Symmetric Sets in Non-compact Rank One Symmetric Space, J. Geom. Anal., 2026
AMS Western Sectional Meeting, Special Session on Geometric Analysis, November 2026
Geometry and Topology Seminar, UC Riverside, May 2026
Soul and Shape: Metric Structures and Geometric Analysis, Lightning talk, University of Oklahoma, April 2026
AMS Western Sectional Meeting, Special Session on Recent developments in geometric analysis, March 2026
Pure Math Seminar, Hong Kong University of Science and Technology, July 2025
Math Department Seminar, South China University of Technology, July 2025
Youtube Channel of Instituto de Matemática Pura e Aplicada (IMPA): https://www.youtube.com/user/impabr