美国伊利诺伊大学教授宋仁明学术报告 9月23日上午

发布时间:2020-09-18浏览次数:605

概率统计系列讲座六:

报告题目:【Potential Theory of Markov Processes with Jump Kernels Decaying at the Boundary】

时间:2020年9月23日 (星期三)上午 09:00

地点:腾讯会议(会议ID: 511 3889 6273)

主讲:美国伊利诺伊大学教授,宋仁明

主办:数学与信息学院

参加对象:统计系老师与学生


报告摘要:In this talk I will present some recent results on the potential theory of Markov processes with jump kernels decaying at the boundary of its state space $\mathbb R^d_+$, the upper half space  of $\mathbb R^d$. The jump kernel is of the form $J^D(x, y)=|x-y|^{-d-\alpha}B(x, y)$, where $\alpha\in (0, 2)$ and $B(x, y)$, which involves three parameters $\beta_1, \beta_2$ and $\beta_2$,  tends to 0 when $x$  or $y$ tends to the boundary. We assume that the killing function is of the form  $\kappa(x)=cx_d^{-\alpha}$. Our main result is a boundary Harnack principle which says that, for any  $p>(\alpha-1)_+$, there are  values of $\beta_1, \beta_2, \beta_3$ and the constant $c$ such that  nonnegative harmonic functions of the process must decay at the rate $x^p_d$ if they vanish near a  certain portion of the boundary. We also have examples showing that there are values of  $\beta_1, \beta_2, \beta_3$ for which the boundary Harnack principle fails. 

This talk is based on a  joint paper with Panki Kim and Zoran Vondracek.