报告人：Dima Ryabogin（肯特州立大学）

邀请人：张宁

报告时间：2022年6月7日 （星期二）21: 00-23:00  

报告地点：Zoom ID: 632 5110 1950（Passcode: 610092）

报告题目：Ulam's problem 19 from the Scottish Book and related problems.

报告摘要：Ulam's Problem 19 from the Scottish Book  asks is a solid of uniform density which will float in water in every position a sphere?Assuming that the density of water is $1$, one can show  that there exists a  strictly convex    body of revolution $K\subset {\mathbb R^3}$of uniform density $\frac{1}{2}$, which is not a Euclidean ball,  yet  floats in equilibrium in every orientation. We will discuss this and related problems suggested by Croft, Falconer and Guy.

报告人简介：Dima Ryabogin，肯特州立大学教授，凸几何分析，应用调和分析专家；其文章多发表于Ann. Math.、JAMS、Adv. Math.等优秀期刊上。