More forcing notions imply diamond

نویسندگان

  • Andrzej Roslanowski
  • Saharon Shelah
چکیده

We prove that the Sacks forcing collapses the continuum onto d, answering the question of Carlson and Laver. Next we prove that if a proper forcing of the size at most continuum collapses ω2 then it forces ♦ω1 . Research partially supported by KBN 654/2/91 Research partially supported by “Basic Research Foundation” administered by The Israel Academy of Sciences and Humanities. Publication 475.

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1 5 A ug 1 99 4 More forcing notions imply diamond

We prove that the Sacks forcing collapses the continuum onto d, answering the question of Carlson and Laver. Next we prove that if a proper forcing of the size at most continuum collapses ω2 then it forces ♦ω1. Research partially supported by KBN 654/2/91 Research partially supported by “Basic Research Foundation” administered by The Israel Academy of Sciences and Humanities. Publication 475.

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عنوان ژورنال:
  • Arch. Math. Log.

دوره 35  شماره 

صفحات  -

تاریخ انتشار 1996