English

Generalized Tukey reducibility between $\sigma$-directed sets

Logic 2025-07-11 v1

Abstract

We introduce the pre-Tukey reducibility, a generalization of the Tukey reducibility between directed sets that works well in ZF\mathsf{ZF}. We investigate the pre-Tukey reducibility between several σ\sigma-directed sets under assumptions on sets of reals, which hold in the Solovay model and in L(R)L(\mathbb{R}) satisfying AD\mathsf{AD}.

Cite

@article{arxiv.2507.07309,
  title  = {Generalized Tukey reducibility between $\sigma$-directed sets},
  author = {Hiroshi Sakai and Toshimasa Tanno},
  journal= {arXiv preprint arXiv:2507.07309},
  year   = {2025}
}

Comments

19 pages

R2 v1 2026-07-01T03:54:00.691Z