Speaker	：Osamu Kobayashi (Osaka University)
Title	：閉曲線の共形的長さと山辺の共形不変量
	（Abstract）
Date	：March 8 (Tue.) 2016, 14：45～16：15
Place	：Dept. of Mathematics, Sci. Bldg., F404
Top
Speaker	：Saki Okuhara　(OCAMI)
Title	：The tt*-Toda equation and loop groups
	（Abstract）
Date	：February 23 (Tue), 2016, 14：45～16：15
Place	：Dept. of Mathematics, Sci. Bldg., F415
Top
Speaker	：Hong Van Le　（Institute of Mathematics of ASCR, Czech Republic（Professor））
Title	：Deformation of Lagrangian submanifolds in strict nearly Kaehler 6-manifolds
	（Abstract）
Date	：December 2 (Wed.), 2015　14：45～16：15
Place	：Dept. of Mathematics, Sci. Bldg., F415
Top
Speaker	：Eliot Fried　（OIST）
Title	：(1) Shape transitions in some systems involving line and surface energy ：(2) Kinematics and energetics of unstretchable two-dimensiona elastic bodies
	（Abstract）
Date	： October 14 (Wed.) (1) 14：45　～　15：45 (2) 16：00　～　17：00
Place	：Dept. of Mathematics, Sci. Bldg., F415
Top
Speaker	：Andreas Arvanitoyeorgos　（University of Patras, Greece）
Title	：The normalized Ricci flow on some homogeneous spaces under a dynamical point of view
	（Abstract）PDF
Date	：April 22 (Wed.) 14：45～16：15
Place	：Dept. of Mathematics, Sci. Bldg., F415
Top
Speaker	：Shigeyasu Kamiya　(Osakacity University)
Title	：２次元複素双曲空間に作用する複素双曲三角群について
	（Abstract）
Date	：April 15 (Wed.) 16：45～18：15
Place	：Dept. of Mathematics, Sci. Bldg., F415
Top

Laguerre 幾何の方法を用いて球面上の閉曲線の 共形不変な長さを定義する．これをもとに 2000年の和田昌昭氏との 共同研究で得られた Schwarz 微分を用い，Riemann 多様体上の閉曲線に 対して共形的長さを定義する．これから得られる Riemann 多様体の 不変量と山辺の共形不変量との関係について述べたい．

Top

Bolton, Pedit and Woodward showed in 1995 that the Toda equations correspond to harmonic maps of Riemann surface into the complex projective spaces via loop groups. We will explain an analogy for the tt*-Toda equations in this talk.

Top

Deformation of Lagrangian submanifolds in strict nearly Kaehler 6-manifolds Abstract: Lagrangian submanifolds in strict nearly Kaehler 6-manifolds $M^6$ are related to special Lagrangian submanifolds in Calabi-Yau 6-manifolds and coassociative cones in $G_2$-manifolds. In my talk I shall explain the reduction of the deformation problem of Lagrangian submanifolds in the smooth category to the deformation problem in the real analytic category and derive its consequences. I also compare our result with a consideration by Lotay for the case $M^ 6 = S^6$ and discuss some related open problems. A part of my talk is based on our joint preprint with Lorenz Schwachhoefer (arXiv:1408.6433).

Top

(1) We will present a variational problem that combines the challenges of creating aesthetically pleasing space curves and constructing area minimizing surfaces. The problem consists of finding energetically preferred equilibrium configurations of a system consisting of a closed, inextensible, unshearable loop endowed with elastic resistance to bending that is spanned by a liquid film endowed with constant surface tension. Aside from presenting results from bifurcation and stability analyses based on the first and second variations of the relevant energy functional, we will provide results for various generalizations of the problem.

(2) We will present a variational theory for two-dimensional bodies that are unstretchable in the sense that they are capable of sustaining only isometric deformations. Aside from the relevant Euler--Lagrange equations,we will derive boundary conditions and consider applications to ribbons and Moebius bands.

Top

２次元複素双曲空間$H_{\bf C}^{2}$の３つのcomplex geodesics $C_{j}$ (j=1,2,3)それぞれを固定点集合にする３つのcomplex reflections $i_{j}$ (j=1,2,3) から生成される群$\Gamma$を複素双曲三角群(complex hyperbolic triangle group)という。初めに２次元複素双曲空間$H_{\bf C}^{2}$　およびこの空間に作用する群$PU(1,2;\mathbb{C})$の元の性質などについて説明し、次に複素双曲三角群（特に$(n,n,\infty)$ 型の複素双曲三角群）の離散性について議論する。

Top