The axiom of determinateness implies has precisely two countably complete, uniform, weakly normal ultrafilters
The strength of the projective Martin conjecture
We show that Martin’s conjecture on Π¹₁ functions uniformly -order preserving on a cone implies Π¹₁ Turing Determinacy over ZF + DC. In addition, it is also proved that for n ≥ 0, this conjecture for uniformly degree invariant functions is equivalent over ZFC to -Axiom of Determinacy. As a corollary, the consistency of the conjecture for uniformly degree invariant Π¹₁ functions implies the consistency of the existence of a Woodin cardinal.
Weak Rudin-Keisler reductions on projective ideals
We consider a slightly modified form of the standard Rudin-Keisler order on ideals and demonstrate the existence of complete (with respect to this order) ideals in various projective classes. Using our methods, we obtain a simple proof of Hjorth’s theorem on the existence of a complete Π¹₁ equivalence relation. This proof enables us (under PD) to generalize Hjorth’s result to the classes of equivalence relations.
Нестандартный анализ и аксиома детерминированности
Сильно минимальные модули над дистстрибутивными справа кольцами