On a theorem by Juh\'asz and Szentmikl\'ossy

Abstract

We extend a theorem by Juh\'asz and Szentmikl\'ossy to notions related to pseudocompactness. We also allow the case when one of the cardinals under consideration is singular. We give an application to the study of decomposable ultrafilters: if \kappa\ is singular, D is a uniform ultrafilter over \kappa ^+, and D' is a uniform ultrafilter over cf \kappa, then D' \times D is \kappa-decomposable.