学术报告
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From the Centro-Affine Minkowski Problem to the Logarithmic Minkowski Inequal...We consider the logarithmic Minkowski inequality which is equivalent to several problems in convex geometric analysis and is still an open problem in dimension greater than 2. Among the problems equivalent to the logarithmic Minkowski inequality is the uniqueness of solutions to the logarithmic Minkowski problem. We present yet a new connection to a uniqueness of a Minkowski problem, namely if a given centro-affine Minkowski problem has unique solution (up to special linear group of transformations), then the corresponding logarithmic Minkowski inequality holds.Prof. Alina Stancu (Concordia University Canada)致远楼101室2019 年 09 月25 日 10:00-11:00
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Stochastic Symplectic Methods and Numerical Ergodicity of Stochastic Nonlinea...In this talk we present a review on stochastic symplecticity (multi-symplecticity) and ergodicity of numerical methods for stochastic nonlinear Schrödinger (NLS) equation. The equation considered is charge conservative and has the multi-symplectic conservation law. Based a stochastic version of variational principle, we show that the phase flow of the equation, considered as an evolution equation, preserves the symplectic structure of the phase space. We give some symplectic integrators and multi-symplectic methods for the equation. By constructing control system and invariant control set, it is proved that the symplectic integrator, based on the central difference scheme, possesses a unique invariant measure on the unit sphere.洪佳林 研究员(中国科学院 数学与系统科学研究院)致远楼101室2019年9月17日 16:00-17:00
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Variational Implicit-Solvent Predictions of the Dry–Wet Transition Pathways ...Ligand–receptor binding and unbinding are fundamental biomolecular processes and particularly essential to drug efficacy. Environmental water fluctuations, however, impact the corresponding thermodynamics and kinetics and thereby challenge theoretical descriptions. We devise a holistic, implicit-solvent, multi- method approach to predict the (un)binding kinetics for a generic ligand–pocket model. We use the variational implicit-solvent model (VISM) to calculate the solute–solvent interfacial structures and the corresponding free energies, and combine the VISM with the string method to obtain the minimum energy paths and transition states between the various metastable (“dry” and “wet”) hydration states.周圣高 副教授 (苏州大学)致远楼101室2019年9月9日 10:30-11:30
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Rigidity of Center Lyapunov Exponents and Su-IntegrabilityLet f be a conservative partially hyperbolic diffeomorphism which is homotopic to an Anosov automorphism A on T 3 . We show that the stable and unstable bundles of f are jointly integrable if and only if every periodic point of f admits the same center Lyapunov exponent with A. In particular, f is Anosov. This implies that every conservative partially hyperbolic diffeomorphism which is homotopic to an Anosov automorphism on T 3 is ergodic, which proves the Ergodic Conjecture proposed by Hertz-Hertz-Ures on T 3 . This is a joint work with Shaobo Gan.史逸 研究员(北京大学)宁静楼104室2019年8月28日11:00-12:00
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Some Progress on Studying Dynamical Systems beyond Uniform HyperbolicityThe study of Dynamical Systems is mainly concerned with orbit structure, specifically long term or asymptotic behavior, for maps or flows. Uniformly Hyperbolic systems are standard examples of complex or chaotic systems. However, uniformly hyperbolic systems are not dense in the space of all dynamical systems. After that people tried to know the world beyond uniform hyperbolicity for which there are many open questions proposed by Bowen, Palis etc. In this talk we will introduce some progress on Bowen's one question to search specification-like properties and statistical properties and Palis SRB conjecture to search the existence of SRB measures.田学廷 教授 (复旦大学)宁静楼104室2019年8月28日10:00-11:00
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Algebraic Birkhoff Factorization and Group Action in RenormalizationThe Algebraic Birkhoff Factorization (ABF) of Connes and Kreimer gives an algebraic formulation of the renormalization process in quantum field theory. Their ABF is an factorization of an algebra homomorphism from a Hopf algebra to a Rota-Baxter algebra. This algebraic formulation facilitates the mathematical study in renormalization and allows the renormalization method to be applied to problems in mathematics.Professor Li Guo (Rutgers University Newark)致远楼108室2019年8月26日 9:30-10:30
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On a Non-local Curvature Flow Arising From the Hele-Shaw ProblemWe consider long time behavior of a given smooth convex embedded closed curve evolving according to a non-local curvature flow, which arises in a Hele-Shaw problem and has a prescribed rate of change in its enclosed area A (t), i.e. , where is given. Specifically, when the enclosed area expands at any fixed rate, i.e. or decreases at a fixed rate one has the round circle as the unique asymptotic shape of the evolving curves; while for a sufficiently large rate of area decrease, one can have n-fold symmetric curves (which look like regular polygons with smooth corners) as extinction shapes (self-similar solutions).Professor Tsai Dong-Ho (中国台湾清华大学)致远楼101室2019年8月21日10:00-11:00
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The Regular Representation of a Quantum Linear SupergroupUsing quantum differential operators, we construct a super representation for the quantum linear supergroup on a certain polynomial superalgebra. We then extend the representation to its formal power series algebra which contains a submodule isomorphic to the regular representation of the supergroup. In this way, we obtain a new presentation of the supergroup by a basis together with explicit multiplication formulas of the basis elements by generators.杜杰 教授 (新南威尔士大学)致远楼108室2019年7月22日 9:30-10:30