Hi! I'm Herng Yi (that's my first name), a Mathematics Ph.D. candidate and Vanier Scholar at the University of Toronto. My advisors are Regina Rotman and Alexander Nabutovsky. I completed a B.Sc. in Mathematics at MIT. I'm current applying for postdoctoral positions that begin Fall 2026 or later. (CV)

Research Interests

My research interests lie in Quantitative Topology. I study bounds on the sizes or quantities of geodesics and sweepouts in Riemannian manifolds. My work also involves bounding the geometric complexity of topological constructions such as cohomology operations and homotopy groups.

Selected Articles

2025 Geometric constructions of mod p cohomology operations. arXiv:2510.12574, 70 pg.
2025 (Joint with Omar Alshawa) Riemannian 3-spheres that are hard to sweep out by short curves. arXiv:2501.10904, 21 pg.
2022 Stable closed geodesics and stable figure-eights in convex hypersurfaces. arXiv:2203.07166, 32 pg.

Upcoming Talks

Oct 28 U. Chicago, Geometric Analysis Seminar
Oct 30 U. Chicago, No Boundaries/Geometry & Topology Seminar
Nov 6 UIUC, Geometric Analysis Seminar

Teaching

2024. 2025 Writing Consultant, Writing NSERC Research Proposals, Graduate Centre for Academic Communication
2024 Course Instructor, MAT223S Linear Algebra I
2021 Mentor, Teaching Assistant Mentorship Programme

Service

2025 Founder, Newsletter of the Mathematics Graduate Student Association
2023 Cofounder, Bird's Eye Conference
2020-21 Diversity and Equity Committee, Dept. of Mathematics, University of Toronto
2017-18 MIT Open Access Task Force​

Banner photo credit: Heejong Lee