Borel Tukey morphisms and combinatorial cardinal invariants of the continuum
Logic
2019-08-16 v2
Abstract
We discuss the Borel Tukey ordering on cardinal invariants of the continuum. We observe that this ordering makes sense for a larger class of cardinals than has previously been considered. We then provide a Borel version of a large portion of van Douwen's diagram. For instance, although the usual proof of the inequality does not provide a Borel Tukey map, we show that in fact there is one. Afterwards, we revisit a result of Mildenberger concerning a generalization of the unsplitting and splitting numbers. Lastly, we show that the inclusion ordering on embeds into the Borel Tukey ordering on cardinal invariants.
Keywords
Cite
@article{arxiv.1208.1788,
title = {Borel Tukey morphisms and combinatorial cardinal invariants of the continuum},
author = {Samuel Coskey and Tamás Mátrai and Juris Steprāns},
journal= {arXiv preprint arXiv:1208.1788},
year = {2019}
}