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arXiv · 1009.1528

The maximal linear extension theorem in second order arithmetic

Alberto Marcone·Richard A. Shore
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Abstract

We show that the maximal linear extension theorem for well partial orders is equivalent over RCA_0 to ATR_0. Analogously, the maximal chain theorem for well partial orders is equivalent to ATR_0 over RCA_0.

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Alberto Marcone, Richard A. Shore. 2011-01-18. The maximal linear extension theorem in second order arithmetic. https://doi.org/10.1007/s00153-011-0231-1

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