복소기하학연구단
Speaker Hoang-Chinh Lu Université Paris-Saclay, Orsay We investigate in depth the behaviour of Monge-Ampère volumes of quasi-psh functions on a given compact hermitian manifold. We prove that the property for these Monge-Ampère volumes to stay bounded away from zero or infinity is a bimeromorphic invariant. We show in particular that a conjecture of …
Speaker Brendan Hassett ICERM / Brown Univ. A complex variety X is rational if its field of meromorphic functions is isomorphic to C(t1, ..., td), the function field of projective space Pd. It is stably rational if X × Pm is rational for some m. Topological and complex invariants give criteria for whether …
Speaker Lukasz Kosinski Jagiellonian University A subset V of a domain Ω has the extension property if for every holomorphic function p on V there is a bounded holomorphic function φ on Ω that agrees with p on V and whose sup-norm on Ω equals the sup-norm of p on V. Within the talk, we …
Speaker Xu Wang NTNU - Norwegian University of Science and Technology We shall give an explicit estimate of the lower bound of the Bergman kernel associated to a positive line bundle. In the compact Riemann surface case, our result can be seen as an explicit version of Tian’s partial C0-estimate.
Speaker Sheng Meng KIAS Let X be a compact complex manifold in Fujiki's class C, i.e., admitting a big (1,1)-class . Consider Aut(X) the group of biholomorphic automorphisms and Aut(X) the subgroup of automorphisms preserving the class via pullback. We show that X admits an Aut(X)-equivariant Kähler model: there is a bimeromorphic holomorphic …
Speaker Sung Rak Choi Yonsei Univ. Choi-Park first introduced and develped the notion of potential pairs. The notion was designed to control the singularities of the outcome of the 'anticanonical' minimal model program. In this talk, after reviewing the properties of potnetial klt pairs, we examine the ACC property of the potential lc …
Speaker Christian Schnell Stony Brook Univ. The theory of variations of Hodge structure has many applications in algebraic geometry. Most of these are based on the results by Schmid, Cattani, Kaplan, Kashiwara, and Kawai from the 1970s and 1980s. I will describe a new approach that proves these results — such as the …
Speaker Ming Xiao UCSD Bounded symmetric domains are an important class of geometric objects in complex analysis and geometry, which possess a high degree of symmetry. They often serve as the model cases in the study of many rigidity phenomena. In this talk, we will discuss two mapping problems between bounded symmetric domains …
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 …
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, …