Profinite properties of graph manifolds
arXiv:0807.3727
Abstract
Let be a closed, orientable, irreducible, geometrizable 3-manifold. We prove that the profinite topology on the fundamental group of is efficient with respect to the JSJ decomposition of . We go on to prove that is good, in the sense of Serre, if all the pieces of the JSJ decomposition are. We also prove that if is a graph manifold then is conjugacy separable.
v2, corrected an error in Lemma 2.3. v3 filled a gap in the proof (see Definition 5.1). 26 pages