Michael Spaces and Ultrafilters

Abstract

A Michael space is a Lindelöf space which has a non-Lindelöf product with the Baire space. In this work, we present the notion of Michael ultrafilter and we use it to construct a Michael space under the existence of a selective ultrafilter and $\max \{\mathfrak{b},\mathfrak{g}\}=\mathfrak{d}$.

12 pages