Tameness phrase

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In mathematics , the conjecture of tameness is a conjecture going back to Albert Marden from the theory of Klein's groups in 3-dimensional topology, which was proven in 2004 by Ian Agol , Danny Calegari and David Gabai .

statement

Every complete , 3-dimensional hyperbolic manifold with a finitely generated fundamental group is topologically tame , that is, it is homeomorphic to the interior of a compact manifold.

Ends of hyperbolic 3-manifolds

From the topological tameness it follows immediately that every orientable, complete 3-dimensional hyperbolic manifold with a finitely generated fundamental group can be broken down into a compact kernel (which is to be homeomorphic ) and finitely many connected "ends" which are of the form . The surfaces are homeomorphic to the connected components of .

Role of hyperbolicity

The assumption that it is hyperbolic plays an essential role in proving the conjecture of tameness. There are counterexamples of (non-hyperbolic) 3-manifolds with finitely generated fundamental groups whose ends are not tame.

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