English

Sequential topologies and Dedekind finite sets

Logic 2021-03-19 v1

Abstract

It is consistent with ZF set theory that the Euclidean topology on the real line is not sequential, yet every infinite set of reals contains a countably infinite subset. This answers a question of Gutierres.

Cite

@article{arxiv.2103.10001,
  title  = {Sequential topologies and Dedekind finite sets},
  author = {Jindrich Zapletal},
  journal= {arXiv preprint arXiv:2103.10001},
  year   = {2021}
}
R2 v1 2026-06-24T00:17:56.933Z