Hyperbolic groups that are not commensurably co-hopfian

Sela proved that every torsion-free one-ended hyperbolic group is co-Hopfian. We prove that there exist torsion-free one-ended hyperbolic groups that are not commensurably co-Hopfian. In particular, we show that the fundamental group of every simple surface amalgam is not commensurably co-Hopfian.

Chi tiết về thư mục
Những tác giả chính: Stark, E, Woodhouse, DJ
Định dạng: Journal article
Ngôn ngữ:English
Được phát hành: Oxford University Press 2020
Miêu tả
Tóm tắt:Sela proved that every torsion-free one-ended hyperbolic group is co-Hopfian. We prove that there exist torsion-free one-ended hyperbolic groups that are not commensurably co-Hopfian. In particular, we show that the fundamental group of every simple surface amalgam is not commensurably co-Hopfian.