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The Theory of Sets of Ordinals

Peter Koepke·Martin Koerwien
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Abstract

We propose a natural theory SO axiomatizing the class of sets of ordinals in a model of ZFC set theory. Both theories possess equal logical strength. Constructibility theory in SO corresponds to a natural recursion theory on ordinals.

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Peter Koepke, Martin Koerwien. 2005-02-13. The Theory of Sets of Ordinals. https://arxiv.org/abs/math/0502265

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