A Proof That All Seifert 3-manifold Groups and All Virtual Surface Groups Are Conjugacy Separable
نویسنده
چکیده
We prove that the fundamental group of any Seifert 3-manifold is conjugacy separable. That is, conjugates may be distinguished in finite quotients or, equivalently, conjugacy classes are closed in the pro-finite topology.
منابع مشابه
Virtual retractions, conjugacy separability and omnipotence
We use wreath products to provide criteria for a group to be conjugacy separable or omnipotent. These criteria are in terms of virtual retractions onto cyclic subgroups. We give two applications: a straightforward topological proof of the theorem of Stebe that infiniteorder elements of Fuchsian groups (of the first type) are conjugacy distinguished, and a proof that surface groups are omnipotent.
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