المستخلص: |
We are interested in complete affinely flat manifolds and in their fundamental groups. Milnor in [8], showed that any virtually polycyclic and torsion-free group is the fundamental group of some complete affinely flat manifold and has conjectured that are the only possible fundamental groups. A few years later, Margulis (see [7]) gave an example, in dimension 3, of a flat Lorentzian manifold whose fundamental group is free (non-abelian), thus giving a counter-example to the Milnor conjecture.
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