Compactness and independence in non first order frameworks

This communication deals with positive model theory, a non first order model theoretic setting which preserves compactness at the cost of giving up negation. Positive model theory deals transparently with hyperimaginaries, and accommodates various analytic structures which defy direct first order treatment. We describe the development of simplicity theory in this setting, and an application to the lovely pairs of models of simple theories without the weak non finite cover property.

• Type: Journal
• Year: 2005
• Where: BSL
• Authors: Itay Ben-Yaacov
• Keywords: BSL 2005, Positive Model Theory, Various Analytic Structures, Weak Non Finite