English

Strong Medvedev reducibilities and the KL-randomness problem

Logic 2022-04-29 v1

Abstract

While it is not known whether each real that is Kolmogorov-Loveland random is Martin-L\"of random, i.e., whether KLRMLR\mathrm{KLR}\subseteq\mathrm{MLR}, Kjos-Hanssen and Webb (2021) showed that MLR\mathrm{MLR} is truth-table Medvedev reducible (s,tt\le_{s,tt}) to KLR\mathrm{KLR}. They did this by studying a natural class Either(MLR) and showing that MLRs,ttEither(MLR)KLR\mathrm{MLR}\le_{s,tt}\mathrm{Either(MLR)}\supseteq\mathrm{KLR}. We show that Degtev's stronger reducibilities (positive and linear) do not suffice for the reduction of MLR to Either(MLR), and some related results.

Cite

@article{arxiv.2204.13297,
  title  = {Strong Medvedev reducibilities and the KL-randomness problem},
  author = {Bjørn Kjos-Hanssen and David J. Webb},
  journal= {arXiv preprint arXiv:2204.13297},
  year   = {2022}
}
R2 v1 2026-06-24T11:01:05.311Z