Seminários de Teoria dos Modelos 12 de Março 2009, 14h00 Eleftheriou will finish the proof of the existence of G00. If time allows, Usvyatsov will prove the following theorem: Let G be a definably compact definably connected abelian group definable in an o-minimal expansion of a field. Then G^{00} is torsion free. The proof splits into two parts: 1. For every definable set X, Stab(X) is a type-definable subgroup of G. This uses some general nonsense about generic sets. 2. Stab(X) is of bounded index in G. This uses dependence and Keisler measures. | back |