English

Adding the constant evasion and constant prediction numbers to Cicho\'n's maximum

Logic 2025-04-21 v2

Abstract

Let e2const\mathfrak{e}^\mathsf{const}_2 be the constant evasion number, that is, the size of the least family Fω2F\subseteq{}^{\omega}2 of reals such that for each predictor π ⁣:<ω22\pi\colon {}^{<\omega}2\to 2 there is xFx\in F which is not constantly predicted by π\pi; and let v2const\mathfrak{v}_2^\mathsf{const} be the constant prediction number, that is, the size of the least family Π2\Pi_2 of functions π ⁣:<ω22\pi\colon {}^{<\omega}2\to 2 such that for each xω2x\in{}^{\omega}2 there is πΠ2\pi\in\Pi_2 that predicts constantly xx. In this work, we show that the constant evasion number e2cons\mathfrak{e}_2^{\mathrm{cons}} and the constant prediction number v2const\mathfrak{v}_2^\mathsf{const} can be added to Cicho\'n's maximum with distinct values.

Cite

@article{arxiv.2503.24185,
  title  = {Adding the constant evasion and constant prediction numbers to Cicho\'n's maximum},
  author = {Miguel A. Cardona and Miroslav Repický and Saharon Shelah},
  journal= {arXiv preprint arXiv:2503.24185},
  year   = {2025}
}

Comments

32 pages, 6 figures

R2 v1 2026-06-28T22:40:44.183Z