应兰州大学数学与统计学院邀请，挪威科技大学的Ehrnstrom教授将于2021年5月28日在线举办专题学术报告。

报告题目:Smooth stationary water waves with exponentially localised vorticity

报告摘要：We construct small-amplitude surface water waves travelling over a large but finite depth in a fluid with concentrated vorticity. The construction is based on a bifurcation-like argument, although one where the bifurcation is rather done from something that is not a water wave solution per se, but a radial and exponentially decaying ground state of a semi-linear elliptic problem in the whole plane.

The proof consists of several parts, where some precise reflection estimates at the surface and flat bed play a major role, as does the fact that everything is exponentially decaying away from the concentrated vorticity. Finally, the vertical replacement of the centre of vorticity with respect to the surface and flat bed is necessary to guarantee a travelling solitary wave whose motion is governed by the very concentrated, but everywhere present, vorticity.

This is joint work with C. Zeng (Georgia Tech) and S. Walsh (Missouri).

时 间：5月28日（星期五）16：00

地 点：理工楼518（Zoom Meeting）

自行参与：ZoomMeeting ID: 988 9383 5100   Password: 241315

Mats Ehrnstrom教授简介

Mats Ehrnstrom，挪威科技大学教授, 挪威皇家科学与文学学会会士,主要从事色散偏微分方程和流体偏微分方程的研究，尤其是在弱色散方程的最高波，孤立波的存在性和正则性方面做了非常出色的工作。他目前已在“Duke Math. J.”、 “J. Eur. Math. Soc.”、“Arch. Ration. Mech. Anal.”、“Ann. Inst. H. Poincaré Anal. Non Linéaire”、“SIAM J. Math. Anal.”等国际重要学术期刊上发表论文多篇。

甘肃省高校应用数学与复杂系统省级重点实验室

数学与统计学院

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2021年5月26日