学术报告
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Inverse Mean Curvature Flow for Space-Like Graphic Hypersurfaces with Boundar...In this talk, we introduce the evolution of space-like graphic hypersurfaces defined over a convex piece of hyperbolic plane〖 H〗^n (1), of center at origin and radius 1, in the (n+1)-dimensional Lorentz-Minkowski space R_1^(n+1) along the inverse mean curvature flow with the vanishing Neumann boundary condition, and show that this flow exists for all the time.毛井 教授(湖北大学)腾讯会议室2021年7月6日 10:00-11:00
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Universal Bounds for Fractional Laplacian on the Bounded Open Domain in R^nLet Ω be a bounded open domain on the Euclidean space R^n. In this talk, we would like to consider the eigenvalues of fractional Laplacian, and establish an inequality of eigenvalues with lower order under certain conditions. We remark that, our eigenvalue inequality is universal and generalizes the eigenvalue inequality for the poly-harmonic operators.曾令忠 副教授 (江西师范大学)腾讯会议室2021年7月6日 11:00-12:00
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Total Squared Mean Curvature of Submanifolds in a Cartan-Hadamard ManifoldThis is an introduction about the recent progress on some open problems and conjectures about the total squred mean curvature in a Cartan-Hadamard manifold. The integral of geodesic curvature of curves represents the beding energy of a spingy wire, the study of which was initiated at the birth of the calculus of variations by J. Bernoulli in 1690s, and was extensively studied by Euler in 1740s. The total squared mean curvature of surfaces, nowdays called the Willmore energy, naturally raised up in the study of vibrating properties of thin plates in the 1810s. We will talk about the relationship of this energy and the first eigenvalue of Laplacian of a submanifold in a negatively curved space..胥世成 教授(首都师范大学)腾讯会议 ID:487 135 2102021年7月6日 14:30-15:30
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On the Willmore Problem for Surfaces with SymmetriesIn 1989, Kusner proposed the generalized Willmore conjecture which states that the Lawson minimal surfaces $\xi_{g,1}$ minimizes uniquely the Willmore energy for all immersions in the 3-sphere with genus g>0. We show that it holds under some symmetric assumption. That is, the conjecture holds if $f:M\rightarrow S^3$ is of genus $g>1$ and is symmetric under the symmetric group $G_{g,1}$ action. Here $G_{g,1}$ denote the symmetric group of $\xi_{g,1}$ generated by reflections of circles of $S^3$, used in Lawson's original construction of $\xi_{g,1}$. This is based on joint works with Prof. Kusner.王鹏 教授(福建师范大学)腾讯会议 ID:487 135 2102021年7月6日 15:30-16:30
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An Introduction to Hyperbolic Dehn FillingsIn these talks, I will briefly survey some development of results on hyperbolic Dehn fillings. I will discuss works of I.Agol and M.Lackenby related to bounds on exceptional Dehn fillings of cusped hyperbolic 3-manifolds.刘毅 教授 (北京大学)宁静楼104室2021年7月2号 9:00-11:00
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Cone Spherical Metrics on Compact Riemann SurfacesCone spherical metrics are constant curvature +1 conformal metrics with finitely many cone singularities on compact Riemann surfaces. Their existence has been an open problem since 1980s. The speaker will talk about the recent progresses on this problem joint with Qing Chen, Yu Feng, Bo Li, Lingguang Li, Yiqian Shi, Jijian Song and Yingyi Wu.致远楼101室2021年7月2日 星期五 13:30-15:30
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Pointed Modular Tensor CategoryA modular tensor category is pointed if every simple object is a simple current. We show that any pointed modular tensor category is equivalent to the module category of a lattice vertex operator algebra. Moreover, if the pointed modular tensor category C is the module category of a twisted Drinfeld double associated to a finite abelian group G and a 3-cocycle with coefficients in U(1), then there exists a selfdual positive definite even lattice L such that G can be realized an automorphism group of lattice vertex operator algebra $V_L,$ $V_L^G$ is also a lattice vertex operator algebra and C is equivalent to the module category of $V_L^G.$ This is a joint work with S. Ng and L. Ren.董崇英 教授(美国加州大学圣克鲁兹分校)致远楼108室2021年6月29日 16:00-16:50
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Super Orbifold TheoryLet V be a vertex operator superalgebra and G a finite automorphism group of V containing the canonical automorphism such that V^G is regular.We classify the irreducible V^G -modules appearing in twisted V -modules and prove that these are all the irreducible V^G -modules. Moreover, the quantum dimensions of irreducible V^G -modules are determined, a global dimension formula for V in terms of twisted modules is obtained and a super quantum Galois theory is established. In addition, the S-matrix of V^G is computed.任丽 研究员 (四川大学)致远楼108室2021年6月29日 17:00-17:50