?? 报告题目：Geometry of Rays and the Compactification of Space of Non-positive Curvature（射线和具有非负曲率空间的紧致化）
报告摘要：
The compactification of a topology space is an important problem in mathematics, and it is how to embed a topological space into a compact space as a dense subset. To do this, there are various kinds of methods, but each is a way of controlling points from “going off to infinity” by in some way adding “points at infinity” or preventing such an “escape”.
???In this talk, we will introduce the compactifications of geodesic spaces of non-positive curvature by Busemann functions and (metric) asymptotic rays, and how such two methods are equivalent to each other.
???报告人：孙磊，讲师，博士
???报告时间：2015年6月3日（星期三）15：440
???报告地点：丹青楼318
???欢迎广大师生参与交流!
En
