Yi Ouyang
yiouyang@ustc.edu.cn
Education
1996-2000 Ph.D. in Mathematic, University of Minnesota (Twin Cities), USA
1995-1996 Doctoral Candidate, Ohio State University, USA
1993-1995 Master's Degree in Pure Mathematics, University of Science and Technology of China
1989-1993 Bachelor's Degree in Mathematics, University of Science and Technology of China
Experience
2021-Present Researcher, Hefei National Laboratory
2006-Present Professor, University of Science and Technology of China
2003-2006 Associate Professor, Tsinghua University
2000-2003 Postdoctoral Fellow, University of Toronto, Canada
Overview of Academic Research
Prof. Ouyang’s research interest is algebraic number theory and arithmetic geometry, and their applications in coding theory and cryptography. He wrote the highly acclaimed book Theory of p-adic Galois Representations with Prof. Jean-Marc Fontaine (member of French Academy of Sciences). He published more than forty research papers, many in the internationally renowned journals Crelle, Comp. Math., Sci. China Math., Math Z., DCC, FFA, Pub. Mat., JNT, CJM, PAMS etc. He obtained important results in arithmetic of elliptic curves and abelian varieties, isogeny-based cryptography, p-adic representation theory of Galois groups and ideal class groups.
His/her major achievements include:
* Developed an inductive methods to show the unboundedness of Tate-Shafarevich groups of a fixed abelian variety over cyclic extensions of global fields which gave a firm answer of an open problem by Prof. Česnavičius at Paris-Saclay;
* Showed the unboundedness of Tate-Shafarevich groups of elliptic curves over number fields over a fixed cyclic extension;
* Classified the local structure of Fp-points in the isogeny graphs of the supersingular elliptic curves and the superspecial abelian surfaces;
* Designed SQIsign 2D2, a signature scheme in the isogeny-based post-quantum cryptography.
Research Directions/Fields:
Isogeny-based post quantum cryptography
Arithmetic of elliptic curves and abelian varieties
Class groups and class numbers of number fields and function fields
Major Honors and Awards
2021 Anhui Provincial Outstanding Teacher
2022 Fok Ying Tung Education Foundation Teaching Award (second class)
2018 Anhui Provincial Master Teacher
2017 Baosteel Excellent Teacher Award
Representative Publications
1. Y. Ouyang. The group cohomology of universal ordinary distribution, J. Reine Angew. Math. 537, 1–32 (2001). Independent Author
2. Y. Ouyang, J. Xie. The growth of Tate-Shafarevich groups in cyclic extensions, Compos. Math. 158, 2014–2032 (2022). Alphabet Order
3. J. Li, Y. Ouyang, Y. Xu. On abelian 2-ramification torsion modules of quadratic fields, Sci. China Math.65, 2459-2482 (2022). Alphabet Order
4. Y.Ouyang, J. Xie. Unboundedness of Tate-Shafarevich groups in fixed cyclic extensions, Math. Z. 307, Paper No. 61 (2024). Alphabet Order
5. Z. Xu, Y. Ouyang*, Z. Zhou. Neighborhood of vertices in the isogeny graph of principally polarized superspecial abelian surfaces, Finite Fields Appl. 103, 102579 (2025). Corresponding Author