Organizing Committee
 Huijun Fan (SMS PKU)
symplectic geometry and mathematical physics, geometric analysis  Sergey Gorchinskiy (MI RAS)
algebra and geometry: algebraic geometry, Ktheory  Hailiang Li (SMS CNU)
fluid mechanics, partial differential equations, analysis  Jinsong Liu (AMSS)
algebraic geometry: singularity theory  Yi Liu (BICMR)
Topology of 3manifolds, hyperbolic geometry  Denis Osipov (MI RAS)
algebraic geometry, number theory, integrable system  Ye Tian (UCAS, AMSS)
Number Theory, Arithmetic Geometry, Iwasawa Theory  Alexey Tuzhilin (MSU)
geometry: Riemannian and metric geometry  Yue Yang (CE PKU)
computation mathematics and mechanics  Ping Zhang (AMSS)
P. D. E.: fluid equation and semiclassical analysis  Alexander Zheglov (MSU)
geometry: algebraic geometry, integrable system
PROGRAM
11:00 (GMT+3)
Sheng Rao Wuhan University 

Bio: Sheng Rao received his PhD from Zhejiang University in 2011 and spent two more years there as a postdoctoral fellow. Then, he joined Wuhan University as a lecturer and has been a full professor since 2019. He is interested in several complex variables and complex geometry, especially deformation theory of complex structures. 
Geometry of logarithmic forms and deformations of complex structures.
We present a new method to solve certain dbarequations for logarithmic differential forms by using harmonic integral theory for currents on Kahler manifolds. As applications, we generalize the result of Deligne about closedness of logarithmic forms, give geometric and simpler proofs of Deligne's degeneracy theorem for the logarithmic Hodge to de Rham spectral sequences at E1level, as well as certain injectivity theorem on compact Kahler manifolds. Our method also plays an important role in CaoPaun's recent works on the extension of pluricanonical sections and proof of Fujino's injectivity conjecture.
Furthermore, for a family of logarithmic deformations of complex structures on Kahler manifolds, we construct the extension for any logarithmic (n,q)form on the central fiber and thus deduce the local stability of log CalabiYau structure by extending an iteration method to the logarithmic forms. Finally we prove the unobstructedness of the deformations of a log CalabiYau pair and a pair on a CalabiYau manifold by differential geometric method. Its projective case was originally obtained by KatzarkovKontsevichPantev in 2008.
This talk is based on a joint work with Kefeng Liu and Xueyuan Wan.
12:00 (GMT+3)
Sergey Suetin MI RAS 

Bio: Sergey Suetin is Doctor of physicomathematical sciences and a Leading Scientific Researcher at Steklov Mathematical Institute of RAS. He is an expert in rational approximation of analytic functions, Pade approximation, inverse theorems, general orthogonal polynomials. 
On extension of a power series outside of its disk of convergence.
The problem of computer extension of power series came from the papers by Milton Van Dyke in the 1970s and is related to the theory of perturbations in fluid mechanics. The seminal Stahl's Theory (19851986) provided the theoretical basis for the use of Pade approximations in solving this problem. The culmination of using Stahl's Theory is the development of HELM by Antonio Trias in 2012.
In the talk, we propose to discuss some other methods of power series extension based on rational HermitePade approximations.
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