Martin’s Axiom and Maximal Orthogonal Families
نویسنده
چکیده
It is shown that Martin’s Axiom for σ-centred partial orders implies that every maximal orthogonal family in R is of size 20 . For x, y ∈ R define the inner product
منابع مشابه
Martin's axiom and almost disjoint families
Assuming Martin’s Axiom and א1 < 2 א0 , we show that, for any κ, λ < 20 and any almost disjoint family {ai : i < λ} of countable subsets of κ, there is a partition {pn : n ∈ ω} of κ so that pn ∩ ai is finite for each 〈i, n〉 ∈ λ × ω.
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