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arXiv · 1110.1907

Relative to any non-hyperarithmetic set

Noam Greenberg·Antonio Montalban·Theodore Slaman
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Abstract

We prove that there is a structure, indeed a linear ordering, whose degree spectrum is the set of all non-hyperarithmetic degrees. We also show that degree spectra can distinguish measure from category.

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Noam Greenberg, Antonio Montalban, Theodore Slaman. 2011-10-10. Relative to any non-hyperarithmetic set. https://arxiv.org/abs/1110.1907

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