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arXiv · 2405.08575

Complexity of codes for Ramsey positive sets

Allison Wang
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Abstract

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

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Allison Wang. 2024-05-14. Complexity of codes for Ramsey positive sets. https://arxiv.org/abs/2405.08575

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