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arXiv · 2604.15894

Long Strong Chains of Subsets of $ω_1$

David Asperó·Curial Gallart
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Abstract

We force the existence of a chain of length $ω_3$ in $[ω_1]^{ω_1}$ increasing modulo finite. The construction involves symmetric systems of models of two types as side conditions, introduced by the second author. This improves previous results of Koszmider and Veličković-Venturi.

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David Asperó, Curial Gallart. 2026-04-17. Long Strong Chains of Subsets of $ω_1$. https://arxiv.org/abs/2604.15894

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