日期 Date |
时间 Time |
地点 Place |
报告人 Speaker |
题目(点击题目可查看摘要) Title(click the title to show the abstract) |
2月28日
28 February
|
13:00 - 14:00 |
数学楼 401 Math. Building 401
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韩京俊(复旦大学) Jingjun Han (Fudan University) |
Abstract: We reduce the termination of flips to the termination of terminal flips and the ACC conjecture for minimal log discrepancies (mlds) of enc pairs. As a consequence, the ACC conjecture for mlds of enc pairs implies the termination of flips in dimension 4.
We show that, in any fixed dimension, the termination of flips follows from the lower-semicontinuity for mlds of terminal pairs, and the ACC for mlds of terminal and enc pairs. Moreover, in dimension 3, we give a rough classification of enc singularities, and prove the ACC for mlds of enc pairs. These two results provide a second proof of the termination of flips in dimension 3 which does not rely on any difficulty function. This is a joint work with Jihao Liu.
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14:30 - 15:30 |
数学楼 401 Math. Building 401
|
焦骏鹏(清华大学) Junpeng Jiao (Tsinghua University) |
Abstract: A Calabi-Yau fibration is a fibration of projective varieties X->Z such that the
canonical bundle K_X is numerically trivial over Z. This class of varieties plays a significant role
in algebraic geometry, appearing naturally in contexts such as good minimal models and
elliptic Calabi-Yau varieties. In this talk, I will present some results on the boundedness of
Calabi-Yau fibrations under certain natural conditions, based on joint work with Minzhe Zhu
and Xiaowei Jiang.
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3月28日
28 March
|
13:00 - 14:00 |
数学楼 102 Math. Building 102
|
李思辰(华东理工大学) Sichen Li (East China University of Science and Technology) |
Abstract: This talk introduces the birational geometry of the automorphisms of projective fibered varieties.
|
14:20 - 15:20 |
数学楼 102 Math. Building 102
|
杜佳宾(上海数学与交叉学科研究院) Jiabin Du (SIMIS) |
Abstract: Let X be a complex smooth projective variety. Roughly speaking, the action of automorphisms group of X on its Chow groups are controlled by the action on cohomology groups predicted by Bloch-Beilinson conjecture.
In this talk, we will introduce this kind of results for surfaces of general type with a genus two fibration. This is a joint work with Wenfei Liu.
|
15:40 - 16:40 |
数学楼 102 Math. Building 102
|
仲国磊(IBS-CGP) Guolei Zhong (IBS-CGP) |
Abstract: A folklore conjecture asserts that a Fano manifold of Picard number one
admitting a non-isomorphic surjective endomorphism is the projective space. This conjecture
is known up to dimension three by Amerik-Rovinsky-Van de Ven and Hwang-Mok
independently. In this talk, I will report our recent progress on this conjecture especially when
the tangent bundle is big. Certain specific dynamical restriction on the positivity of tangent
bundles will also be discussed. This talk is partly based on the joint work with Feng shao.
|
4月10日
10 April
|
13:00-14:00 |
数学楼 102 Math. Building 102 |
徐政(北京大学) Zheng Xu (Peking University) |
Abstract: In this talk, we give an introduction to S.Pande's work on the positive characteristic analogy of Tian's alpha invariant. The main reference is arXiv:2311.00989.
|
14:30-15:30 |
数学楼 102 Math. Building 102 |
缪铭昊(南京大学) Minghao Miao (Nanjing University) |
Abstract: In this talk, I will report Andreasson-Berman's work on a conjectural bounds on the height of arithmetic Fano varieties under the assumption that its complexification is K-semistable. This is inspired by Fujita-Liu's algebro-geometric result that the complex projective space has maximal volume among all K-semistable Fano varieties.
Reference: R. Andreasson and R. Berman, Sharp bounds on the height of K-semistable Fano varieties I, the toric case. arXiv:2205.00730.
|
4月11日
11 April
|
13:00-14:00 |
数学楼 102 Math. Building 102 |
徐政(北京大学) Zheng Xu (Peking University) |
Abstract: The abundance conjecture is one of the most important conjectures in algebraic geometry, particularly in birational geometry. In characteristic 0, it was proven in the 1990s that the conjecture holds for log canonical pairs of dimension 3. In this talk, we will discuss recent progress toward proving the abundance conjecture for threefolds in positive characteristic.
|
14:15-15:15 |
数学楼 102 Math. Building 102 |
陈华一(西湖大学) Huayi Chen (Westlake University) |
Abstract: In this talk, I will explain a joint work with Marion Jeannin, where we establish a general framework of Harder-Narasimhan theory, in which we prove the existence and uniqueness of coprimary filtration.
|
15:45-16:45 |
数学楼 102 Math. Building 102 |
韩骥原(西湖大学) Jiyuan Han (Westlake University) |
Abstract: The weight-cscK metric is initially defined and studied by Lahdili, Apostolov, etc. The definition of such metric could provide a universal framework for the study of different canonical metrics, e.g, extremal metrics, Kahler Ricci soliton metrics, \mu-cscK metrics.
In a joint work with Yaxiong Liu, we prove that on a smooth Kahler manifold X, the G-coercivity of weighted Mabuchi functional implies the existence of weighted-cscK metrics. In particular, there exists a weighted-cscK metric if X is a projective manifold that is weighted K-stable for models.
|
4月12日
12 April
|
13:30-14:30 |
数学楼 102 Math. Building 102 |
缪铭昊(南京大学) Minghao Miao (Nanjing University) |
Abstract: In this talk, I will report the work of Andreasson-Berman on canonical heights of arithmetric log pair with relatively ample (or anti-ample) log canonical line bundle. Canonical heights is defined as the (Arekelov-theoretic) height metrized by the Kahler-Einstein metic on the complexification of infinite place. The main result of Andreasson-Berman's work is the canonical height can be expressed as a limit of periods on the N-fold products, as N tends to infinity. As a corollary, the canonical heights of certain arithmetic log surfaces can be computed explicitly in terms of the Hurwitz zeta function. <\br>
Reference: R. Andreasson and R. Berman, Canonical heights, periods and the Hurwitz zeta function. arXiv:2406.19785.
|
15:00-16:00 |
数学楼 102 Math. Building 102 |
王淋生(复旦大学) Linsheng Wang (Fudan University) |
Abstract: The quintic Del Pezzo manifolds are hyperplane sections of Gr(2,5). It was proved by K. Fujita that the quintic Del Pezzo fourfolds and fivefolds are K-unstable, which are the first examples of K-unstable Fano manifolds of Picard number one. In this talk, I will compute the delta invariants of the quintic Del Pezzo fourfolds and fivefolds. This is a joint work with Yuchen Liu.
|
4月25日
25 April
|
14:00-15:00 |
数学楼 102 Math. Building 102 |
孙锐然(厦门大学) Ruiran Sun (Xiamen University) |
Abstract: Motivated by Shafarevich’s conjecture, Arakelov and Parshin established a significant finiteness result: for any curve C, the set of isomorphism classes of non-constant morphisms C → M_g is finite for g≥2. However, for moduli stacks parametrizing higher-dimensional varieties, the Arakelov-Parshin finiteness theorem fails due to the presence of non-rigid families. In this talk, I will review recent advances in rigidity problems for moduli spaces of polarized manifolds, focusing on two main topics: the 1-pointed rigidity property of moduli spaces of polarized manifolds, as well as the distribution of non-rigid families in moduli spaces.
|
15:30-16:30 |
数学楼 102 Math. Building 102 |
田家骅(华东师范大学) Jiahua Tian (East China Normal University) |
Abstract: Past 50 years have witnessed the marriage of contemporary mathematics and modern physics, with String Theory serving as the central arena for this union. The need for constructing realistic models of our Universe in string theory has been relying heavily on advances of algebraic geometry. I shall in this talk motivate why this marriage is indispensable and introduce basic concepts bridging the two realms. My perspective is inevitably biased, but I hope to inspire the audience to explore the unknowns.
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5月23日
23 May
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6月06日
06 June
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6月20日
20 June
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