On incomparability and related cardinal functions on ultraproducts of Boolean algebras
نویسندگان
چکیده
Let C denote any of the following cardinal characteristics of Boolean algebras: incomparability, spread, character, π-character, hereditary Lindelöf number, hereditary density. It is shown to be consistent that there exists a sequence 〈Bi : i < κ〉 of Boolean algebras and an ultrafilter D on κ such that
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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