Nonexistence of iterated countable meets and joins in the nowhere centered quotient

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Let β=⋀n0<ω⋁n1<ω⋯ωk−1×A(n0,n1,…,nk−1)\beta=\bigwedge_{n_0<\omega}\bigvee_{n_1<\omega}\cdots\omega^{k-1}\times A_{(n_0,n_1,\ldots,n_{k-1})} be the indicated iterated operation on a family of sets {Ax‾∣x‾∈ωk}⊆[ω]ω\{A_{\overline{x}}\mid\overline{x}\in\omega^k\}\subseteq[\omega]^\omega, where 2≤k<ω2\leq k<\omega. Iterated-operation conjecture. For every integer kk with 2≤k<ω2\leq k<\omega, there exists such a family for which β\beta does not exist in P(ωk)/NCk\mathcal{P}(\omega^k)/\mathcal{NC}^k. This would identify a limitation on iterating countable joins and meets in the nowhere centered quotient; the supplied text does not state whether the claim is known or open.

References

Primary source

Mario Jardón Santos, “Small infinite partitions and other features of the Nowhere Centered ideal”, arXiv:2203.00234 (2022).

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