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David Roberts
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c.c.c forcing notions and adding minimal generic reals

Is the following statement consistent:

``There is no non-trivial c.c.c forcing notion adding a minimal generic real''?

The question is related to Prikry's question: Is it consistent that any non-trivial c.c.c forcing notion adds a Cohen real or a Random real?

See also A special c.c.c forcing notion and adding minimal generic reals where it is shown that the answer to the above question is no, if we assume $CH$ or $MA+\neg CH$ (this follows from the results of Judah-Shelah in Forcing Minimal Degree of Constructibility (JSTOR, free author version)) Also it is clear that, a model for Prikry's question is also a model for the above mentioned question.

Remark. By a theorem of Shelah, a modified version of Prikry’s conjecture holds in the context of Souslin c.c.c forcing: i.e. every Souslin c.c.c forcing either adds a Cohen real or is a Maharam algebra. Indeed, Shelah showed that any Souslin c.c.c forcing which is not $ω^ω$-bounding adds a Cohen real. See

S. Shelah, How special are Cohen and random forcing. Israel Journal of Math. 88 (1-3), pp. 159-174, (1994), doi:10.1007/BF02937509, arXiv:math/9303208, author pdf

Mohammad Golshani
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