A countable-support symmetric iteration separating PP from AC

Abstract

We construct, from a ground model of ZFC, a transitive symmetric model M satisfying ZF + DC + PP + ACwo + AC. The construction starts with a Cohen symmetric seed model N over Add(ω,ω1) and performs an Ord-length countable-support symmetric iteration. For fixed parameters S:=Aω and T:=PowerSet(S) (as computed in N), successor stages add orbit-symmetrized packages which force the localized splitting principle PPsplit\! T (hence PP T) and the choice principle ACwo, while preserving DC and keeping A non-well-orderable. A diagonal-lift/diagonal-cancellation scheme produces ω1-complete normal limit filters. A persistence argument yields SVC+(T) in M, and Ryan--Smith localization then upgrades PP T and ACwo to PP.

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