English

Some consequences of $\mathrm{TD}$ and $\mathrm{sTD}$

Logic 2021-08-18 v2

Abstract

Strongly Turing determinacy, or sTD\mathrm{sTD}, says that for any set AA of reals, if xyTx(yA)\forall x\exists y\geq_T x (y\in A), then there is a pointed set PAP\subseteq A. We prove the following consequences of Turing determinacy (TD\mathrm{TD}) and sTD\mathrm{sTD}: (1). ZF+TD\mathrm{ZF+TD} implies weakly dependent choice (wDC\mathrm{wDC}). (2). ZF+sTD\mathrm{ZF+sTD} implies that every set of reals is measurable and has Baire property. (3). ZF+sTD\mathrm{ZF+sTD} implies that every uncountable set of reals has a perfect subset. (4). ZF+sTD\mathrm{ZF+sTD} implies that for any set of reals AA and any ϵ>0\epsilon>0, (a) there is a closed set FAF\subseteq A so that DimH(F)DimH(A)ϵ\mathrm{Dim_H}(F)\geq \mathrm{Dim_H}(A)-\epsilon. (b) there is a closed set FAF\subseteq A so that DimP(F)DimP(A)ϵ\mathrm{Dim_P}(F)\geq \mathrm{Dim_P}(A)-\epsilon.

Keywords

Cite

@article{arxiv.2107.10470,
  title  = {Some consequences of $\mathrm{TD}$ and $\mathrm{sTD}$},
  author = {Yinhe Peng and Liuzhen Wu and Liang Yu},
  journal= {arXiv preprint arXiv:2107.10470},
  year   = {2021}
}

Comments

Better version

R2 v1 2026-06-24T04:25:10.533Z