Changho Han

About me: I am a Postdoctoral Fellow at the University of Waterloo. My research is primarily in algebraic geometry. In particular, I am mainly interested in geometric and arithmetic properties of moduli spaces, and also interested in enumerative problems. See my research statement for more details on my mathematical interests.

Starting Fall 2024, I will move to Korea University as an Assistant Professor (Tenure-Track).

I got PhD degree in Mathematics at Harvard University. My graduate advisor is Joe Harris.

I was a Limited-Term Assistant Professor at the University of Georgia.

Here is my CV.

Papers and preprints

• Arithmetic secant formulae for linear series on hyperelliptic curves, with Ethan Cotterill and Naizhen Zhang.
  (in preparation).


• Counting points on $x^2+y^2 = z^4$ and 5-isogenies of elliptic curves over $\mathbb{Q}$, with Santiago Arango-Pi˜neros, Oana Padurariu, and Sun Woo Park.
  (in preparation).


• Stable quadrics, admissible covers, and Kondo’s sextic K3 surfaces, with Anand Deopurkar.
  (in preparation).


• Extending the Torelli map to alternative compactifications of the moduli space of curves, with Jesse Kass and Matthew Satriano.
  (in preparation).


• Arithmetic inflection of superelliptic curves, with Ethan Cotterill, Ignacio Darago, Cristhian Garay López, and Tony Shaska.
  Under revision at Michigan Mathematical Journal. pdf, arXiv


• Compact moduli of K3 surfaces with a nonsymplectic automorphism, with Valery Alexeev and Philip Engel.
  Transactions of the American Mathematical Society Series B, 11 (2024). pp. 144-163. Online, pdf, arXiv


• Arithmetic inflection formulae for linear series on hyperelliptic curves, with Ethan Cotterill and Ignacio Darago.
  Mathematische Nachrichten, 00 (2023). pp. 1-29. Online, pdf, arXiv


• Enumerating odd-degree hyperelliptic curves and abelian surfaces over $\mathbb{P}^1$, with June Park.
  Mathematische Zeitschrift, 304 (2023). Article no. 5. Online, Publisher's Correction, pdf, arXiv


• Stable log surfaces, admissible covers, and canonical curves of genus 4, with Anand Deopurkar.
  Transactions of the American Mathematical Society, 374 (2021). no. 1, pp. 589-641. Online, pdf, arXiv, Thesis


• Arithmetic of the moduli of semistable elliptic surfaces, with June Park.
  Mathematische Annalen, 375 (2019). pp 1745-1760. Online, pdf, arXiv

Teaching

I have taught the following at the University of Waterloo:

• Pmath 464/764, as an instructor (Introduction to Algebraic Geometry), Winter 2024


• Amath/Pmath 331, as an instructor (Applied Real Analysis), Fall 2023


• Amath/Pmath 332, as an instructor (Applied Complex Analysis), Winter 2023


• Math 127, as an instructor (Calculus 1 for the Sciences), Fall 2022

I have taught the following at the University of Georgia:

• Math 2700, as an instructor (Elementary Differential Equations), Spring 2022


• Math 2250, as an instructor (Calculus I), Fall 2021


• Math 2700, as an instructor (Elementary Differential Equations), Spring 2021


• Math 2250, as an instructor (Calculus I), Fall 2020


• Math 2250, as an instructor (Calculus I), Spring 2020


• Math 1113, as an instructor (precalculus), Fall 2019

I have taught the following courses at Harvard:

• Math 1b, as a coaching fellow (integration, series and differential equations) and as a teaching fellow, Spring 2019


• Math 1b, as a teaching fellow (integration, series and differential equations), Fall 2017


• Math 21b, as a teaching fellow (linear algebra and differential equations), Spring 2017


• Math 258Y, as a course assistant (graduate topics course on degenerations in algebraic geometry), Fall 2016


• Math 1b, as a teaching fellow (integration, series and differential equations), Fall 2015