Proof-theoretic strengths of the well ordering principles

Toshiyasu Arai

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arXiv · 1811.09964

Proof-theoretic strengths of the well ordering principles

Toshiyasu Arai

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Abstract

In this note the proof-theoretic ordinal of the well-ordering principle for the normal functions ${\sf g}$ on ordinals is shown to be equal to the least fixed point of ${\sf g}$. Moreover corrections to the previous paper are made.

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BibTeX RIS

Toshiyasu Arai. 2018-11-25. Proof-theoretic strengths of the well ordering principles. https://arxiv.org/abs/1811.09964

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