A model-theoretic Baire category theorem for simple theories and its applications

摘要

We prove a model-theoretic Baire category theorem for T_(low) ~(～f) -sets in a countable simple theory in which the extension property is first-order and show some of its applications. We also prove a trichotomy for minimal types in countable nfcp theories: either every type that is internal in a minimal type is essentially 1-based by means of the forking topologies, or T interprets an infinite definable 1-based group of finite D-rank or T interprets a strongly minimal formula.