English

Hydras for $\omega_{1}$

Logic 2018-02-20 v3

Abstract

In this paper we introduce a hydra battle. Each hydra will eventually die out, but the fact is not provable in a set theory with urelements of natural numbers and the assumption that `there exists an uncountable regular ordinal'.

Cite

@article{arxiv.1508.01548,
  title  = {Hydras for $\omega_{1}$},
  author = {Toshiyasu Arai},
  journal= {arXiv preprint arXiv:1508.01548},
  year   = {2018}
}
R2 v1 2026-06-22T10:28:14.427Z