Geometry and Topology Seminar——Embedding spaces of arcs and the mapping class groups of 4-manifolds
报告人：谢羿（304am永利集团）
时间：2025-04-02 15:10-17:00
地点：智华楼四元厅
【摘要】
In recent years, the embedding spaces of arcs in 4-manifolds have played a significant role in the study of 4-dimensional topology. For instance, the first and second homotopy groups of the embedding spaces of arcs are used to define the Dax invariant for embedded 2-disks and Budney-Gabai’s W3 invariant for embedded 3-disks, respectively. In this talk, we will generalize these invariants and use them to demonstrate that the mapping class groups of certain 4-manifolds are infinitely generated. These manifolds include some bordered 4-manifolds with 1-handles and the product of a 2-sphere with a surface of positive genus. This is joint work with Jianfeng Lin and Boyu Zhang.
