Abstract

We show Shelah's original creature forcing from 1984 strongly preserves tight mad families. In particular, answering questions of Fischer and Friedman and Friedman and Zdomskyy, we show the constellation ℵ1=a<s=ℵ2\aleph_1 = \mathfrak{a} < \mathfrak{s} = \aleph_2 is consistent with the existence of a Δ31Δ_3^1 wellorder of the reals and tight mad families of sizes ℵ1,ℵ2\aleph_1, \aleph_2 which are Π11,Π21Π_1^1, Π_2^1-definable, respectively. Each of these projective definitions is of minimal possible complexity.

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