복소기하학연구단
Speaker Luca Rizzi IBS-CCG Given a semistable fibration f : X → B I will show a correspondence between foliations on X and local systems on B. Building up on this correspondence we will find conditions that give maximal rationally connected fibrations in terms of data on the foliation. We will develop the …
Jinhyun Park (박진현) Visitor (2022.8.15-2023.8.14) from KAIST Office: B248
Speaker Guolei Zhong IBS-CCG As a fundamental building block of the equivariant minimal model program, the rationally connected variety plays a significant role in the classification of projective varieties admitting non-isomorphic endomorphisms. Twenty years ago, Nakayama confirmed Sato’s conjecture that, a smooth projective rational surface is toric if and only if it admits …
Speaker Ziquan Zhuang Johns Hopkins U Several years ago, Chi Li introduced the local volume of a klt singularity in his work on K-stability. The local-global analogy between klt singularities and Fano varieties, together with recent study in K-stability lead to the conjecture that klt singularities whose local volumes are bounded away from …
Speaker Benjamin McMillan IBS-CCG The Killing operator in (semi) Riemannian geometry has well understood kernel: the infinitesimal symmetries of a given metric. At the next level, the range of the Killing operator can be interpreted as those perturbations of the metric that result from a mere change of coordinates---in contexts like general relativity, …
Speaker Jakub Witaszek Princeton U What allowed for many developments in algebraic geometry and commutative algebra was a discovery of the notion of a Frobenius splitting, which, briefly speaking, detects how pathological positive characteristic Fano and Calabi-Yau varieties can be. Recently, Yobuko introduced a more general concept, a quasi-F-splitting, which captures much more …
Speakers Young-Jun Choi (Pusan National U.) Yoshinori Hashimoto (Osaka Metropolitan U.) Dano Kim (Seoul National U.) Takayuki Koike (Osaka Metropolitan U.) Seungjae Lee (IBS-CCG) Nguyen Ngoc Cuong (KAIST) Mihai Paun (Bayreuth U.) Martin Sera (Kyoto U. Advanced Science) Jihun Yum (IBS-CCG) Schedule Oct. 5 Infinitesimal extension of twisted canonical forms and …
Speaker Pak Tung Ho Sogang University In this talk, I will explain what the weighted Yamabe problem is, and mention some related results that Jinwoo Shin (KIAS) and I obtained.
Speaker Aeryeong Seo Kyungpook National University TBA
Speaker Jinhyun Park KAIST The classical reciprocity theorem, also called the residue theorem, states that the sum of the residues of a rational (meromorphic) differential form on a compact Riemann surface is zero. Its generalization to smooth projective curves over a field is often called the Tate reciprocity theorem. There is a different …
Speaker Jaewoo Jeong IBS CCG The Hankel index of a real variety is a semi-algebraic invariant that quantifies the (structural) difference between nonnegative quadrics and sums of squares on the variety. Note that the Hankel index of a variety is difficult to compute and was computed for just few cases. In 2017, …
