Separating principles below Ramsey's Theorem for Pairs

Manuel Lerman; Reed Solomon; Henry Towsner

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arXiv · 1302.0828

Separating principles below Ramsey's Theorem for Pairs

Manuel Lerman·Reed Solomon·Henry Towsner

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Abstract

In recent years, there has been a substantial amount of work in reverse mathematics concerning natural mathematical principles that are provable from $\RT$, Ramsey's Theorem for Pairs. These principles tend to fall outside of the "big five" systems of reverse mathematics and a complicated picture of subsystems below $\RT$ has emerged. In this paper, we answer two open questions concerning these subsystems, specifically that $\ADS$ is not equivalent to $\CAC$ and that $\EM$ is not equivalent to $\RT$.

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BibTeX RIS

Manuel Lerman, Reed Solomon, Henry Towsner. 2013-02-04. Separating principles below Ramsey's Theorem for Pairs. https://arxiv.org/abs/1302.0828

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