Home >> Seminar 

Subgroup separability and subgroup distortion of 3manifold groups
Hongbin Sun Assistant Professor(Rutgers University)
Saturday, June 13th, 2020, 8:30 AM ZOOM房间号：会议 ID：274 175 4144 

报告时间：2020年6月13日08：3010：00
直播平台：ZOOM房间号：会议 ID：274 175 4144 密码：930643
直播链接：https://cernet.zoom.com.cn/j/2741754144?pwd=TzRiV0gwT2l0NU1CRWtmODlpRUdrZz09
报告内容摘要：For a (finitely generated) subgroup of a (finitely generated) group, we will consider two properties of this subgroup: the separability of this group and its subgroup distortion. The separability of a subgroup measures whether the property of an element not lying in this subgroup is visible by taking some finite quotient. We will give a characterization on whether a subgroup of a 3manifold group is separable. The subgroup distortion compares the intrinsic and extrinsic geometry of a subgroup. For an arbitrary subgroup of a 3manifold group, we prove that the subgroup distortion can only be linear, quadratic, exponential and double exponential. It turns out the subgroup separability and subgroup distortion are closed related for subgroups of 3manifold groups. The subgroup distortion part is joint work with Hoang Nguyen (at BICMR).



