Transfinite dependent choice and ω-model reflection
Christian Rüede · Journal of Symbolic Logic · 2002
Abstract In this paper we present some metapredicative subsystems of analysis. We deal with reflection principles, ω-model existence axioms (limit axioms) and axioms asserting the existence of hierarchies. We show several equivalences among the introduced subsystems. In particular we prove the equivalence of Σ11 transfinite dependent choice and Π21 reflection on ω-models of Σ11-DC.