2021 Spring AGEA ZOOM SEMINARS

2021 Spring AGEA ZOOM SEMINARS
2021-03-05 15:00-16:00(Beijing Time)

This is a joint effort of many algebraic geometers in East Asia. We aim to create a platform for algebraic geometers and students for further interaction and cooperation. 
The seminar will take place on Friday at GMT 1:00 or GMT 7:00, unless otherwise specified, in order to accommodate most participants in East Asia. 
To receive the announcement and the Zoom password, please send an empty mail with the title "Subscription" to the following address:ageaseminar@gmail.com
From March to May 2021, this seminar is run by Morningside Center of Mathematics.
For previous talks, please visit the following pages:
 
Organizing Committee: 
Yujiro Kawamata, Xiaotao Sun, JongHae Keum, Jungkai Chen, Conan Leung,Phung Ho Hai, De-Qi Zhang, Yusuke Nakamura, Baohua Fu, Kiryong Chung, Hsueh-Yung Lin.
 
Supported by MCM and NCTS
 
Upcoming Talks:

Speaker: Junyi Xie (CNRS Rennes)

Time: 15:0016:00  3/05/2021  

Title: Some boundedness problems in Cremona group

Abstract: This talk is based on a work with Cantat and Deserti. According to the degree sequence, there are 4 types (elliptic, Jonquieres, Halphen and Loxodromic) of elements f in Bir(P^2).  For a fixed degree d>=1, we study the set of these 4 types of elements of degree d. We show that for Halphen twists and Loxodromic transformations, such sets are constructible. This statement is not true for elliptic and Jonquieres elements.We also show that for a Jonquieres or Halphen twist f of degree d, the degree of the unique f-invariant pencil is bounded by a constant depending on d. This result may be considered as a positive answer to the Poincare problem of bounding the degree of first integrals,but for birational twists instead of algebraic foliations. As a consequence of this, we show that for two Halphen twists f and g, if they are conjugate in Bir(f), then they are conjugate by some element of degree bounded by a constant depending on deg(f)+deg(g). This statement is not true for Jonquieres twists. 


Speaker: Guolei Zhong(National University of Singapore)

Time: 16:15–17:15  3/05/2021  

Title: Fano threefolds and fourfolds admitting non-isomorphic endomorphisms.

Abstract: In this talk, we first show that a smooth Fano threefold X admits a non-isomorphic surjective endomorphism if and only if X is either toric or a product of a smooth rational curve and a del Pezzo surface. Second, we show that a smooth Fano fourfold Y with a conic bundle structure is toric if and only if Y admits an amplified endomorphism. The first part is a joint work with Sheng Meng and De-Qi Zhang, and the second part is a joint work with Jia jia. 


Speaker: Zhiyuan Li ( Shanghai Center for Mathematical Sciences)

Time: 9:0010:00  3/19/2021  

Title: TBA

Abstract: TBA


Speaker: Michael Kemeny (University of Wisconsin-Madison)

Time: 10:15–11:15  3/19/2021 

Title: TBA

Abstract: TBA

 

Speaker: Weizhe Zheng (Morningside Center of Mathematics)

Time: 15:0016:00  4/02/2021 

Title: TBA

Abstract: TBA

 

Speaker: Kestutis Cesnavicius (U. Paris Sud)

Time: 16:15–17:15  4/02/2021   

Title: TBA

Abstract: TBA

 

Speaker:  Kuan-Wen Lai (University of Massachusetts Amherst)

Time: 9:00–10:00  4/16/2021

Title: TBA

Abstract: TBA


Speaker: Yu-Shen Lin (Boston University)

Time: 10:15–11:15  4/16/2021

Title: TBA

Abstract: TBA

 

Speaker: Yi Gu (Suzhou University)

Time: 15:0016:00  4/30/2021

Title: TBA

Abstract: TBA


Speaker: Takehiko Yasuda (Osaka University)

Time: 16:15–17:15  4/30/2021

Title: TBA

Abstract: TBA


Speaker: Yuji Odaka (Kyoto University)

Time: 15:00–16:00  5/14/2021

Title: TBA

Abstract: TBA


Speaker: YongJoo Shin (Chungnam National University)

Time: 16:15–17:15  5/14/2021

Title: TBA

Abstract: TBA


Speaker: Zhiyu Tian (BICMR-Beijing University)

Time: 15:00–16:00  5/28/2021

Title: TBA

Abstract: TBA


Speaker: Joao Pedro dos Santos (Universite de Paris)

Time: 16:1517:15  5/28/2021

Title: TBA 

Abstract: TBA