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arXiv · 1408.2845

Superhighness

André Nies·Bjørn Kjos-Hanssen
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Abstract

We prove that superhigh sets can be jump traceable, answering a question of Cole and Simpson. On the other hand, we show that such sets cannot be weakly 2-random. We also study the class superhigh$^\Diamond$, and show that it contains some, but not all, of the noncomputable $K$-trivial sets.

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BibTeXRIS

André Nies, Bjørn Kjos-Hanssen. 2014-08-12. Superhighness. https://doi.org/10.1215/00294527-2009-020

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