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Complexity of codes for Ramsey positive sets

Logic 2024-12-18 v2

Abstract

Sabok showed that the set of codes for GδG_\delta Ramsey positive subsets of [ω]ω[\omega]^\omega is Σ21\mathbf{\Sigma}^1_2-complete. We extend this result by providing sufficient conditions for the set of codes for GδG_\delta Ramsey positive subsets of an arbitrary topological Ramsey space to be Σ21\mathbf{\Sigma}^1_2-complete.

Cite

@article{arxiv.2405.08575,
  title  = {Complexity of codes for Ramsey positive sets},
  author = {Allison Wang},
  journal= {arXiv preprint arXiv:2405.08575},
  year   = {2024}
}
R2 v1 2026-06-28T16:26:53.142Z