Constructing Boolean Algebras for Cardinal Invariants
نویسنده
چکیده
We construct Boolean Algebras answering some questions of J. Donald Monk on cardinal invariants. The results are proved in ZFC (rather than giving consistency results). We deal with the existence of superatomic Boolean Algebras with “few automorphisms”, with entangled sequences of linear orders, and with semi-ZFC examples of the non-attainment of the spread (and hL,hd).
منابع مشابه
Cardinal invariants of ultraproducts of Boolean algebras
We deal with some of problems posed by Monk [Mo 1], [Mo 3] and related to cardinal invariant of ultraproducts of Boolean algebras. We also introduce and investigate several new cardinal invariants. AMS 1991 Mathematics Subject Classification primary: 03G05, 03E05, secondary: 06E15, 03E35 ∗ The research was partially supported by DFG grant Ko 490/7-1. This is publication number 534 of the second...
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تاریخ انتشار 2001