English

On Borel semifilters

General Topology 2016-06-08 v2 Logic

Abstract

Building on work of van Engelen and van Mill, we show that a zero-dimensional Borel space is homeomorphic to a semifilter if and only if it is homogeneous and not locally compact. Under Σ11\mathbf{\Sigma}^1_1-Determinacy, this result extends to all analytic and coanalytic spaces.

Keywords

Cite

@article{arxiv.1605.01024,
  title  = {On Borel semifilters},
  author = {Andrea Medini},
  journal= {arXiv preprint arXiv:1605.01024},
  year   = {2016}
}

Comments

20 pages

R2 v1 2026-06-22T13:52:27.728Z