Elementary submodels of parametrizable models.
Exercices sur la stabilité
Existentially closed II₁ factors
We examine the properties of existentially closed (-embeddable) II₁ factors. In particular, we use the fact that every automorphism of an existentially closed (-embeddable) II₁ factor is approximately inner to prove that Th() is not model-complete. We also show that Th() is complete for both finite and infinite forcing and use the latter result to prove that there exist continuum many nonisomorphic existentially closed models of Th().