Abstract
We investigate higher-dimensional \(\Delta\)-systems indexed by finite sets of ordinals, isolating a particular definition thereof and proving a higher-dimensional version of the classical \(\Delta\)-system lemma. We focus in particular on systems that consist of sets of ordinals, in which case useful order-theoretic uniformities can be ensured. We then present three applications of these higher-dimensional \(\Delta\)-systems to problems involving the interplay between forcing and partition relations on the reals.
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We thank the anonymous referee for an exceptionally thorough and careful reading and a great number of corrections and suggestions that have significantly improved the exposition of the paper.
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Lambie-Hanson, C. Higher-dimensional Delta-systems. Order 40, 173–197 (2023). https://doi.org/10.1007/s11083-022-09602-w
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DOI: https://doi.org/10.1007/s11083-022-09602-w