报告人：Henri Berestycki, EHESS, Paris
报告人简介:Henri Berestycki，法国社会科学高等研究院教授,美国艺术与科学学院外籍院士，美国数学会Fellow. 荣获多项学术奖励和荣誉，如法国科学院的Sophie Germain Prize，德国洪堡基金会的Humboldt Prize, 以及法国荣誉军团骑士勋章。
报告题目：Propagation in reaction-diffusion equations with obstacles: The effect of geometry
摘要：This talk is about travelling fronts going through an array of obstacles for reaction-diffusion equations. I will consider the setting of bistable type equations and periodic obstacles. One can also think of a wave going through a perforated wall. We show in general that the wave is either blocked or it invades the domain. This hinges on results related to a celebrated conjecture of De Giorgi regarding stable solutions of elliptic equations in unbounded domains. I will then describe geometric conditions on the obstacles under which there is either blocking or propagation. I report here on joint work with F. Hamel and H. Matano. I will also recall earlier joint work with L. Caffarelli and L. Nirenberg.
报告时间：7月18日, 16:30-18:00(Harbin), 10:30-12:00(Paris)
Zoom webinar ID: 973 5094 3628