복소기하학연구단
Speaker Dae-Won Lee Ewha Womans University This talk provides a brief survey of recent results and applications concerning the anticanonical minimal model program. Furthermore, we present examples of varieties that admit an anticanonical minimal model despite not being Mori dream spaces. This talk is based on joint work with Sung Rak Choi, Sungwook …
Speakers Shigeyuki Kondo (Nagoya University) JongHae Keum (KIAS) Fei Si (Xi’an Jiaotong University) Kyoung-Seog Lee (POSTECH) Sang-Bum Yoo (Gongju National University of Education) Junchao Shentu (USTC) Haesong Seo (IBS-CCG/KAIST) Minzhe Zhu (KIAS) Yen-An Chen (KIAS) Abstracts PDF file Schedule May 27(Wed) 15:00-16:00, Shigeyuki Kondo 16:30-17:30, JongHae Keum May 28(Thu) 11:00-12:00, Fei Si 13:30-14:30, Kyoung-Seog Lee …
Speaker Hyunmoon Kim Ewha Womans University We present a quadratic Morse-Bott function on the real Grassmannian of a symplectic vector space from a compatible linear complex structure. Its stable manifolds generalize the Lagrangian, symplectic, isotropic, and coisotropic Grassmannians to include the Grassmannians of linear subspaces that are neither isotropic, coisotropic, nor symplectic. The …
Speaker Yan Li Beijing Institute of Technology Let $G$ be a connected, reductive, linear algebraic group that acts on a normal variety $X$, and $B$ be a Borel subgroup group of $G$. The complexity of the $G$-action on $X$ was defined by E. B. Vinberg in 1985 as the codimension of $B$-orbit at …
Speaker Yan Li Beijing Institute of Technology Let $G$ be a connected, reductive, linear algebraic group that acts on a normal variety $X$, and $B$ be a Borel subgroup group of $G$. The complexity of the $G$-action on $X$ was defined by E. B. Vinberg in 1985 as the codimension of $B$-orbit at …
Speaker Daebeom Choi University of Pennsylvania In this talk, we discuss the existence and nonexistence of certain birational contractions of \(\overline{\mathrm{M}}_{g,n}\). Somewhat surprisingly, this depends on the characteristic of the base field: many such contractions exist only in positive characteristic. We present a precise form of this phenomenon and discuss two examples that …
Speaker Yunhyung Cho Sungkyunkwan University It is well known that there is a bijective correspondence between the set of positive integer solutions to the Markov equation and the set of Fano triangles mutation equivalent to the Fano triangle of $\mathbb{P}^2$. In this talk, we establish a higher dimensional generalization of this correspondence for …
Speaker Sung Gi Park Princeton University I will discuss the indeterminacy locus of the period map from the moduli space of hypersurfaces to the period domain and its compactifications. In the case of quartic K3 surfaces, the result verifies the expectation of Laza and O'Grady that the period map from the GIT compactification …
Speaker Hyunsuk Kim University of Michigan Considering the singular cohomology of a cubic fourfold yields a morphism from the moduli space of (smooth) cubic fourfolds to the period domain. Both spaces have natural compactifications, the GIT moduli space of cubic fourfolds parametrizing all GIT polystable objects, and the Baily-Borel compactification of the period …
Speaker Sönke Rollenske Marburg University In the study of (relatively minimal) elliptic surfaces $f\colon S \to C$ with a section, the Weierstrass model plays an important role. We discuss two different models for elliptic surfaces with a bisection (or more generally an $f$-nef divisor which has degree two on the fibres): a birational …
Speaker Sönke Rollenske Marburg University Compact quotients of non-abelian complex nilpotent Lie groups are non-Kähler manifolds with trivial canonical bundle, the most prominent example being the Iwasawa manifold. We give a precise characterisation of the (rare) cases where deformations of such manifolds are unobstructed in terms of so-called verbal ideals in free nilpotent …
Speaker Xian Wu Yonsei University We begin with an overview of the framework of KSBA (Kollár—Shepherd-Barron—Alexeev) moduli spaces and stable degenerations, emphasizing some phenomena that distinguish the higher-dimensional cases from the Deligne–Mumford moduli of stable curves. We then survey several existing explicit constructions of KSBA compactifications. As a detailed example, we discuss the …