Seung-Yeon Ryoo (유승연, 柳昇延)

Hausdorff Center for Mathematics
University of Bonn

I am a postdoctoral researcher at the Hausdorff Center for Mathematics at the University of Bonn. From 2023 to 2026 I was a postdoctoral teaching fellow in the Department of Mathematics at the California Institute of Technology. I received my Ph.D. in 2023 from Princeton University under the supervision of Professor Assaf Naor.

CV

Research interests

• Metric geometry of nilpotent Lie groups.
• Bilipschitz and snowflake embeddings of metric spaces into Euclidean and L^p spaces.
• Mathematical models of synchronization, with an emphasis on the Winfree and Kuramoto models.

Publications and preprints

Metric geometry

1. Asymptotics of Riemannian Lie groups with nilpotency step 2 (with Enrico Le Donne, Luca Nalon, Sebastiano Nicolussi Golo). arXiv preprint
2. Quantitative nonembeddability of groups of polynomial growth into uniformly convex spaces. J. Funct. Anal. 291, 111491 (2026). doi arXiv
3. On the sharpness of the Assouad embedding theorem for finitely generated groups of polynomial growth and nilpotent Lie groups. Doctoral dissertation, Princeton University (2023). ProQuest
4. Embedding snowflakes of Carnot groups into bounded dimensional Euclidean spaces with optimal distortion. Anal. PDE 15, 1933–1990 (2022). doi arXiv

Synchronization dynamics

1. Relaxation dynamics of Winfree oscillators on Riemannian manifolds (with Seung-Yeal Ha, Chaejoo Lee, Eunjun Lee, Jaemoon Lee). arXiv preprint
2. Relaxation dynamics of the inertial Winfree model (with Caiman Moreno-Earle and Grace To). arXiv preprint
3. Emergent behaviors of Winfree oscillators on special orthogonal group (with Seung-Yeal Ha, Chaejoo Lee, Eunjun Lee, Jaemoon Lee). arXiv preprint
4. On oscillator death in the Winfree model. arXiv preprint
5. Quantitative relaxation dynamics from generic initial configurations in the Kuramoto model (with Hangjun Cho, Jiu-Gang Dong, and Seung-Yeal Ha). arXiv preprint
6. Inertia perturbation theory for the inertial Kuramoto model (with Hangjun Cho, Jiu-Gang Dong, and Seung-Yeal Ha). SIAM J. Math. Anal. 58(4) 3669–3719 (2026). doi arXiv
7. Asymptotic formation and orbital stability of phase-locked states in Kuramoto–Lohe type synchronization models on Lie groups. Commun. Math. Sci. 23, 1221–1239 (2025). doi arXiv
8. Constants of motion for the Lohe model with frustration and its applications to emergent dynamics (with Seung-Yeal Ha, Dohyun Kim, Hansol Park). Physica D 416, 132781 (2021). doi arXiv
9. Asymptotic phase-locking dynamics and critical coupling strength for the Kuramoto model (with Seung-Yeal Ha). Commun. Math. Phys. 377, 811–857 (2020). doi arXiv
10. On the relaxation dynamics of Lohe oscillators on some Riemannian manifolds (with Seung-Yeal Ha, Dongnam Ko). J. Stat. Phys. 172, 1427–1478 (2018). doi
11. Emergence of partial locking states from the ensemble of Winfree oscillators (with Seung-Yeal Ha, Dongnam Ko, Jinyeong Park). Quart. Appl. Math. 75, 39–68 (2017). doi
12. Emergent dynamics of a generalized Lohe model on some class of Lie groups (with Seung-Yeal Ha, Dongnam Ko). J. Stat. Phys. 168, 171–207 (2017). doi
13. On the finiteness of collisions and phase-locked states for the Kuramoto model (with Seung-Yeal Ha, Hwa Kil Kim). J. Stat. Phys. 163, 1394–1424 (2016). doi
14. Emergence of phase-locked states for the Kuramoto model in a large coupling regime (with Seung-Yeal Ha, Hwa Kil Kim). Commun. Math. Sci. 14, 1073–1091 (2016). doi
15. On the emergence and orbital stability of phase-locked states for the Lohe model (with Seung-Yeal Ha). J. Stat. Phys. 163, 411–439 (2016). doi
16. Emergent dynamics of Winfree oscillators on locally coupled networks (with Seung-Yeal Ha, Dongnam Ko, Jinyeong Park). J. Differential Equations 260, 4203–4236 (2016). doi
17. Emergence of phase-locked states for the Winfree model in a large coupling regime (with Seung-Yeal Ha, Jinyeong Park). Discrete Contin. Dyn. Syst. 35, 3417–3436 (2015). doi

Teaching

At Caltech, 2025–26:

• Spring: Ma 109c, Introduction to Geometry and Topology
• Fall: Ma 109a, Introduction to Geometry and Topology

Earlier teaching

Last updated September 21, 2026