Turing degrees and randomness for continuous measures

Mingyang Li1,2, Jan Reimann1
1Department of Mathematics, Penn State University, University Park, USA
2Tencent, Shenzhen, China

Tóm tắt

We study degree-theoretic properties of reals that are not random with respect to any continuous probability measure (NCR). To this end, we introduce a family of generalized Hausdorff measures based on the iterates of the “dissipation” function of a continuous measure and study the effective nullsets given by the corresponding Solovay tests. We introduce two constructions that preserve non-randomness with respect to a given continuous measure. This enables us to prove the existence of NCR reals in a number of Turing degrees. In particular, we show that every $$\Delta ^0_2$$ -degree contains an NCR element.

Tài liệu tham khảo

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