On a theorem by Juhász and Szentmiklóssy

Paolo Lipparini

Published 2013-05-08, updated 2013-05-22Version 2

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.