Algebraic topology. Homotopy theory. And applications. I think about configuration spaces (and their variants) of points in spaces and using them to probe questions in algebra, geometry and topology.
Kaufmann, Ralph M.; Zhang, Yongheng Permutohedral structures on E2-operads. Forum Math. 29 (2017), no. 6, 1371-1411.
Zhang, Yongheng Circle deformation in Hacon's sphere eversion. Bridges Conf. Proc., Online, Aug 2021, 265-268.
Wei, Annie; Zhang, Yongheng Wave, Boy's Surface, and Machine. Bridges Conf. Proc., Aalto, Aug 2022, 17-24.
Current Teaching (Fall 2022)
- MATH 105 Calculus with Algebra
- MATH 211 Multivariable Calculus
Regular Office Hours
- M W 10-10:50 AM
- M W Th 1-2:50 PM
- SMUD 510
- MATH 105 Calculus with Algebra (f19)
- MATH 111 Introduction to the Calculus (f15)
- MATH 211 Multivariable Calculus (f15, s16, f16, s17, f17, s18, f18, s19, f19, s20, f20, s21, f21, s22)
- MATH 260 Differential Equations (s18: fiction by Cindy Lopez)
- MATH 345 Functions of a Complex Variable (f16: poem by Greg Carroll, f18: online game by Sai Chauhan)
- MATH 350 Groups, Rings and Fields (f17, s19)
- MATH 355 Introduction to Analysis (s16, s20)
- MATH 455 Topology (s17: 50 lessons [90MB] 50 lessons without notes [20MB])
Teaching at Purdue
- Geometry for Elementary Teachers
- Topology for High School Students (notes by Hannah Burnau)
- Calculus I, II, III
- Linear Algebra
- ODE and basic PDE