Welcome to Fei Si’s Homepage

Welcome to Fei Si’s Homepage

About me:

Now I am a Postdoc at BICMR. Before I was a Phd student at SCMS, Fudan University under supervision Prof. Meng Chen and Prof. Zhiyuan Li.

Research Interest: algebraic geometry and related topics. Currently I work on some explicit compactifications of moduli spaces and their birational geometry, also cohomology and cycle theory on these moduli spaces.

My CV is here.

Email: sifei@bicmr.pku.edu.cn

Office Number = Quan Eulernumber(K3)

Some Personal Notes:

1.Lehn’s conjecture. PDF version of Notes of Porf. Pandharipande’s distingushed lecture at SCMS, Fall 2018.

2.GIT. My reading notes on GIT.

3.Notes on Projective model of K3. My reading notes on projective model of K3 surfaces.

warning: some of the notes are not complete. I will revisit !


  1. Cohomology of moduli space of cubic fourfolds I. Acta Mathematica Sinica, English Series (2022)
  2. Compactifications of moduli space of K3 surfaces of degree 6, with Francois Greer, Radu Laza, Zhiyuan Li, Zhiyu Tian. in preparation (draft available).
  3. K-moduli of log del pezzo pairs, with Long Pan and Haoyu Wu.
  4. Birational geometry of moduli space of del Pezzo pairs, with Long Pan and Haoyu Wu.
  5. Chow ring of moduli spaces of quasi-polarised K3 surfaces in lower genus
  6. Asymptotic Behaviors of Moduli of One-dimensional Sheaves on Surfaces, with Feinuo Zhang.

Invited talks and Slides

  1. Compatifications of moduli spaces of K3 surfaces of degree 6, East Asian Core Doctoral Forum on Mathematics 2020 January 14-17, 2020, Kavli IPMU, Tokyo Slide.
  2. Birational geometry of moduli space of low genus K3 surfaces. When Number Theory meets Algebraic Geometry, USTC, HeFei, 2021.4.19-4.23 Notes of the talk .
  3. Cohomology of compact moduli spaces of cubic 4-folds. 2021.9.15, Algebraic geometry seminar at CAS.
  4. Birational geometry of moduli spaces of K3 surfaces. 2021.12.31, Postdoc Seminar at BICMR.
  5. K-moduli spaces of del pezzo pairs. 2023.4.26, Algebraic geometry seminar at Beijing normal university.
  6. K-moduli spaces of del pezzo pairs. 2023.6.1 Online Nottingham algebraic geometry seminar.
  7. Birational Geometry of Moduli Spaces of Del Pezzo Surface Pairs, 2023.10.17 AG seminar, MCM.
  8. K-moduli spaces of del pezzo pairs. 2023.11.24, AG seminar, MSRC, CQUT. Slide.
  9. Moduli of K3 Surfaces and K-moduli of Fano Pairs, 2023.12.20, AG seminar, Xiamen university.
  10. Cohomology of moduli spaces of cubic 4-folds, 2023.12.27, Seminar on “Moduli Spaces and Related Topics”, YMSC
  11. Some explicit K-moduli spaces I, II. 2024.4.29, 4.30. ChongQing university.


  1. In Fall 2020, We have a reading seminar on the construction of K-moduli spaces. Here is the schedule.

  2. In 2021.6.28-6.30, we have a reading goup on curves on K3s at SCMS Room 406.

  3. In spring of 2022, we have a reading seminar on HyperKahler manifolds at Quanzhai 29, BICMR. The schedule is here.

  4. In spring of 2023, we have a reading seminar on hyperholomorphic sheaves on Wednesday at room 77201, BICMR and here is the schedule.

  5. From 2023 April , we have a seminar on K-moduli theory at BICMR, Quan29, each Friday afternoon. A related birational geometry reading seminar in Tsinghua.

  6. From 2023 October, we have a reading seminar on moduli spaces of boundary polarised CY.

  7. In the spring of 2024, we have a online reading seminar on cohomology of moduli spaces of sheaves on surface.


In 2022.9, I give a mini-course on K3 surface at BICMR. Noetes for the course: Lecture 1. Lecture 2. Lecture 3,4. Lecture 5,6.

Some codes

Python code for wall crossings of K-moduli: walls on F1, walls on BlP(1,1,4)

Sage code on computations of modular forms on locally symmetric varieties by Haoyu Wu: Modular form.

A Python code checking GIT stability on (3,2)-complete intersections in P^3 by Haoyu Wu: GIT(3,2)

学术搜索 arxiv.AG AG.current month AG.new Mathscinet Mathariv

Enumerative geometers:

Rahul Qizheng Okounkov Thomas Joyce Bridgeland Eskin Farb Bryan Behrend Konstevich Gromov

Birational and complex geometers:

Jiangchen Xu Yuchen Alexeev Hacon Birkar Mckernan Kollar ChiLi Donaldson Demailly

IHS Voisin Huybrechtz Debarre Macri Hassett

Arithmetic geometers and Representation theorists: Scholze Venkatesh Tsimerman Tschinkel Yun Zhang wei Zhangshouwu deJong Esnault Bruinier Lan