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Consistency of lim^2 A_kappa at the continuum

Determine whether it is consistent with ZFC that lim^2 A_κ = 0 when κ = 2^{ℵ_0}, i.e., establish the consistency of the vanishing of the second derived limit of the inverse system A_κ at the cardinality of the continuum.

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Background

Beyond the global question for all cardinals, the authors highlight a specific instance targeting κ equal to the continuum 2{ℵ_0}. This focuses on the second derived limit, lim2, whose behavior is known to have deep set-theoretic significance.

Achieving lim2 A_{2{ℵ_0}} = 0 would align with models where higher derived limits vanish, but the consistency of this particular case remains unsettled.

References

We now conclude with some questions that remain open. A specific instance of Question \ref{main_quest} of interest is the following: Is it consistent that \$\lim2\mathbf{A}_{2{\aleph_0}=0\$?

All you need is $\mathbf{A}_κ$ (2506.14185 - Bannister, 17 Jun 2025) in Section 4: Questions