Separability of double cosets and conjugacy classes in 3-manifold groups

Emily Hamilton, Henry Wilton, Pavel Zalesskii

Let M = H^3 / Γbe a hyperbolic 3-manifold of finite volume. We show that if H and K are abelian subgroups of Γand g is in Γ, then the double coset HgK is separable in Γ. As a conse…