Separation problems and forcing∗

نویسنده

  • Jindřich Zapletal
چکیده

Certain separation problems in descriptive set theory correspond to a forcing preservation property, with a fusion type infinite game associated to it. As an application, it is consistent with the axioms of set theory that the circle T can be covered by א1 many closed sets of uniqueness while a much larger number of H-sets is necessary to cover it.

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تاریخ انتشار 2013