Define a complete family of
parent (ancestor) manifolds to be a set of compact 3-manifolds such that every closed
orientable 3-manifold can be obtained by one (or more) Dehn fillings of the manifolds
in the family. In 1983, R. Myers proved that the set of 1-cusped hyperbolic
3-manifolds is a complete family of parent manifolds. We prove this result in a new
way and then go on to prove:
Theorem 1
(a) Let V 0 be any positive real number. Then the set of 1-cusped hyperbolic
3-manifolds of volume greater than V 0 is a complete family of parent manifolds.
(b) Let V 1 be any positive real number. Then the set of 1-cusped hyperbolic
3-manifolds of cusp volume greater than V 1 is a complete family of parent
manifolds.
(c) The set of 2-cusped hyperbolic 3-manifolds containing embedded totally
geodesic surfaces is a complete family of ancestor (actually grandparent)
manifolds.
(d) For any positive integer N, the set of hyperbolic 3-manifolds, each of which
shares its volume with N or more other hyperbolic 3-manifolds, is a complete family
of ancestor manifolds.
As a corollary to Theorem 1(b), we prove that there exists a complete family of
parent manifolds such that at most one Dehn filling on each manifold in the family
yields a manifold of finite fundamental group.
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