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تسجيل مستخدم جديدProfinite properties of graph manifolds
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Let $M$ be a closed, orientable, irreducible, geometrizable 3-manifold. We prove that the profinite topology on the fundamental group of $pi_1(M)$ is efficient with respect to the JSJ decomposition of $M$. We go on to prove that $pi_1(M)$ is good, in the sense of Serre, if all the pieces of the JSJ decomposition are. We also prove that if $M$ is a graph manifold then $pi_1(M)$ is conjugacy separable.
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