Proper forcing extensions and Solovay models

نویسندگان

  • Joan Bagaria
  • Roger Bosch
چکیده

We study the preservation of the property of L(R) being a Solovay model under proper projective forcing extensions. We show that every ∼ 1 3 strongly-proper forcing notion preserves this property. This yields that the consistency strength of the absoluteness of L(R) under ∼ 1 3 strongly-proper forcing notions is that of the existence of an inaccessible cardinal. Further, the absoluteness of L(R) under projective strongly-proper forcing notions is consistent relative to the existence of a ∼ω cardinal. We also show that the consistency strength of the absoluteness of L(R) under forcing extensions with σ-linked forcing notions is exactly that of the existence of a Mahlo cardinal, in contrast with the general ccc case, which requires a weakly-compact cardinal.

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عنوان ژورنال:
  • Arch. Math. Log.

دوره 43  شماره 

صفحات  -

تاریخ انتشار 2004