Patrick Lei

笔记

我在哥伦比亚大学、马萨诸塞大学、波士顿学院和 Simons 中心的课程与讨论班上整理的笔记,均为 PDF。

  • Summer 2026

    Log GLSM and related topics

    These are notes from the summer school "Log GLSM and advances in enumerative geometry" at Sichuan University, Meishan campus in July 2026.

    Sichuan University
  • Jan 2025

    Higher genus GW theory

    What does it take to prove enumerative mirror symmetry for the quintic 3-fold in higher genus? Find out more about recent breakthroughs here.

    Simons Center
  • Spring 2024

    Blowup formula in GW theory

    How do GW invariants change under birational transformations? Learn about Iritani's work on the subject here.

    Columbia
  • Summer 2023

    Simons Summer Math Workshop 2023

    Covers log GW theory in both the algebraic and symplectic settings, topological recursion and the spin GW/Hurwitz correspondence, and Givental-Teleman reconstruction of semisimple CohFTs.

    Simons Center
  • Summer 2022

    Integrability, enumerative geometry, quantization

    Covers enumerative geometry (GW/Hurwitz, GW/DT, quantum K-theory) and (quantum) integrable systems (KdV, W-constraints, etc).

    Simons Center
  • Spring 2026

    Good moduli spaces, positivity, and rationality

    When does an Artin stack admit a "reasonable" moduli space and when does this moduli space have nice properties (for example being (quasi-)projective, rational, etc)?

    Boston College
  • Spring 2026

    Geometric rep theory and universal centralizers

    Covers the geometry of complex semisimple Lie groups (Springer theory, wonderful/toroidal compactifications) before moving on to universal centralizers (and their geometry, mirror symmetry, etc).

    Boston College
  • Fall 2021

    Moduli spaces and hyperkähler manifolds

    Covers hyperkähler manifolds, their geometry, some constructions, and moduli spaces of sheaves on K3 surfaces.

    Columbia
  • Spring 2021

    Minimal Model Program

    Ever wondered how to classify algebraic varieties up to birational equivalence? The MMP is the answer! Covers the basics of the MMP and the MMP in dimension 3.

    Zoom
  • Spring 2021

    Class field theory

    Covers local and global class field theory, including the proofs of the main theorems and some applications.

    Columbia
  • Spring 2021

    Algebraic topology II

    Covers spectral sequences and applications to homotopy groups of spheres, characteristic classes, K-theory, and the Atiyah-Singer index theorem.

    Columbia
  • 2023-24

    The Count of Instantons

    On the mathematics (representation theory, geometry, probability theory) and physics (gauge theory) of instanton counting. Notes partially taken by Davis Lazowski.

    Columbia
  • Fall 2020

    Commutative algebra

    Covers the first part of Matsumura's Commutative Algebra with a focus on dimension theory.

    Columbia
  • Spring 2022

    Informal enumerative geometry seminar

    Covers a variety of topics in enumerative geometry, including GW theory, DT theory, and quantum K-theory and its relationship to geometric representation theory.

    Columbia
  • Spring 2022

    Hyperbolicity

    When is a variety hyperbolic? How many rational points does it have? How many rational curves lie on it? Find out here!

    Columbia
  • Spring 2022

    D-modules and localization

    What is a D-module and how do they appear in representation theory? Learn about the Beilinson-Bernstein localization theorem and the Kazhdan-Lusztig conjectures.

    Columbia
  • Fall 2021

    Hodge theory

    Covers the proof of the existence of mixed Hodge structures for smooth varieties and some applications.

    Columbia
  • Fall 2021

    Deformation theory

    Covers how to deform schemes and sheaves, plus the moduli of stable curves and of coherent sheaves.

    Columbia
  • Fall 2021

    DAHA and knot homology

    What on earth is a double affine Hecke algebra? How does it relate to more familiar mathematics? Find out here!

    Columbia
  • Fall 2021

    Category O

    Covers the basic theory of category O for semisimple Lie algebras, including the Kazhdan-Lusztig conjectures.

    Columbia
  • Spring 2021

    Intersection theory

    Ever wondered what a Chow ring is? Or how to compute intersection numbers on moduli spaces? Find out here!

    Columbia
  • Spring 2021

    Schemes

    Covers schemes, sheaves, and cohomology, mostly following Hartshorne.

    Columbia
  • Spring 2021

    Lie groups and representations II

    Covers invariant theory, Lie algebra cohomology, the cohomology of flag varieties, root systems, and Kac-Moody Lie algebras.

    Columbia
  • Fall 2020

    Geometric invariant theory

    Covers the basics of reductive GIT and applications to moduli spaces of curves.

    Columbia
  • Fall 2020

    FGA explained

    Ever wondered what Grothendieck meant in FGA? Find out here!

    Columbia
  • Fall 2020

    Lie groups and representations I

    Covers the representation theory and classification of semisimple Lie groups.

    Columbia
  • Fall 2020

    Algebraic topology I

    Covers homotopy groups, homology, cohomology, and Poincaré duality.

    Columbia
  • Spring 2020

    Singular spaces

    What is a singularity? How can we measure how bad it is and study its geometry? Find out here!

    UMass
  • Spring 2020

    Symplectic topology

    Covers the basics of symplectic manifolds and some results in the topology of symplectic 4-manifolds.

    UMass
  • Fall 2019

    Lie Algebras

    Covers the basic theory of Lie algebras and the classification and representation theory of semisimple Lie algebras.

    UMass
  • Fall 2019

    Manifolds

    Covers the basic theory of smooth manifolds, differential forms, and de Rham cohomology.

    UMass
  • Spring 2019

    Varieties

    Covers the basic theory of algebraic varieties, including dimension, tangent spaces, and divisors.

    UMass
  • Spring 2019

    Algebra II

    Covers the basic theory of algebraic varieties, including dimension, tangent spaces, and divisors.

    UMass
  • Spring 2019

    Analysis II

    Covers Hilbert and Banach spaces, convergence and compactness in infinite dimensions, and Fourier theory.

    UMass
  • Fall 2018

    Representation theory

    Covers the representation theory of finite groups, Springer theory in type A, and the representation theory and classification of SLn.

    UMass
  • Fall 2018

    Analysis I

    Covers measure theory, the Lebesgue integral, differentiation, and abstract measure theory.

    UMass
  • Spring 2018

    Complex analysis

    Covers the basic theory of holomorphic functions, elliptic functions, and the Riemann mapping theorem.

    UMass