3 papers
math.GT2025
The number of ends of big mapping class groups
Josiah Oh, Yulan Qing, Xiaolei Wu
We analyze the number of ends of the mapping class group of a stable avenue surface. We prove that the mapping class group is one-ended whenever the stable avenue surface has at le…
math.GT2025
Quasi-isometric rigidity for a product of lattices
Josiah Oh
We demonstrate quasi-isometric rigidity for the product of a non-uniform rank one lattice and a nilpotent lattice. Specifically, we show that any finitely-generated group quasi-iso…
math.GR2020
Geometry of non-transitive graphs
Josiah Oh, Mark Pengitore
In this note, we study non-transitive graphs and prove a number of results when they satisfy a coarse version of transitivity. Also, for each finitely generated group , we produ…