主持人：邹燕青

报告人简介：
叶圣奎，2012年获新加坡国立大学博士学位，后在牛津大学做博士后，现为上海纽约大学副教授。研究兴趣在拓扑学领域。文章在发表在Transactions of the American Mathematical Society，Journal of the London Mathematical Society, Israel Journal of Mathematics等期刊。

报告摘要：
For what kind of Aritn groups, it can be writen as a graph of free groups? We will show that for triangle Artin group Art23M splits as a graph of free groups if and only if M is greater than 5 and even. This answers two questions of Jankiewicz in the negative. Combined with the results of Squier and Jankiewicz, this completely determines when a triangle Artin group splits as a graph of free groups. Further applications to polyness will be discussed. This is a joint work with Xiaolei Wu.