Cellularity of free products of Boolean algebras (or topologies)
نویسنده
چکیده
The aim of this paper is to present an answer to Problem 1 of [M1], [M2]. We do this by proving in particular that if μ is a strong limit singular cardinal, θ = (2), 2 = μ then there are Boolean algebras B1,B2 such that c(B1) = μ, c(B2) < θ but c(B1 ∗ B2) = μ. Further we improve this result, deal with the method and the neccessity of the assumptions. The research partially supported by “The Israel Science Foundation” administered by The Israel Academy of Sciences and Humanities. Publication 575. We thank Andrzej Roslanowski for writing sections 1 5 from lectures, 6 7 from notes
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تاریخ انتشار 2008