| 日時 | 4月25日(金) 16:00--18:15 |
|---|---|
| 会場 | 西新プラザ 2階 中会議室 |
| 講師/講演時間 | Miguel Escobedo 氏（バスク大学）/ 16:00--17:00 |
|---|---|
| 題目 | Power laws and Boltzmann equation with soft potential |
| 概要 | Some recent results will be presented on the Boltzmann equation with soft potentials and the role played by powerlaws, via Landau currents. To this end I will briefly explain some of the ideas and arguments of the wave turbulence theory started in the 70's, that serve as strong inspiration of our work. |
| 講師/講演時間 | Ludovico Marini 氏（福岡大学）/ 17:15--18:15 |
|---|---|
| 題目 | Boundedness results for the Riesz transform on Riemannian manifolds |
| 概要 | In this talk, we investigate L^p boundedness properties of the first and second order Riesz transform on Riemannian manifolds. On complete, non-compact manifolds we show their dependence on curvature bounds and large-scale geometry by providing both positive results and counterexamples. This is a joint work with S. Meda, S. Pigola and G. Veronelli (UNIMIB). |
| 日時 | 5月9日(金) 16:00--18:15 |
|---|---|
| 会場 | 西新プラザ 2階 中会議室 |
| 講師/講演時間 | 北川 潤 氏（ミシガン州立大学）/ 16:00--17:00 |
|---|---|
| 題目 | 凸領域の境界上での最適輸送とモンジュ解の存在について |
| 概要 | 本講演ではコスト関数をユークリッド距離の２乗を凸領域の境界へ限定したものとした最適輸送問題を考える．Gangbo-McCannにより球面上であっても写像の形の解（モンジュ解）が存在しない場合があることが知られている．主結果では一定の条件のもとで境界が$C^1$の場合モンジュ解が存在することを示す．本講演はSeonghyeon Jeong氏（National Sun-Yat Sen University）との共同研究に基づく． |
| 講師/講演時間 | 相木 雅次 氏（東京理科大学）/ 17:15--18:15 |
|---|---|
| 題目 | On the Long-time behavior of an Arc-shaped Vortex Filament |
| 概要 | In this talk, we introduce a recent result which investigates the stability of an arc-shaped vortex filament. An arc-shaped filament is an exact solution of an initial-boundary value problem for the Localized Induction Equation, which models the motion of a vortex filament immersed in an incompressible and inviscid fluid. An arc-shaped filament travels along an axis at a constant speed. We show that, in general, perturbations along this axis can grow linearly with respect to time. We also apply these results to investigate the stability of a circular vortex filament, which is an approximation of a vortex ring. |