English

Ultrafilters on singular cardinals of uncountable cofinality

Logic 2019-07-30 v1

Abstract

We prove that consistently there is a singular cardinal κ\kappa of uncountable cofinality such that 2κ2^\kappa is weakly inaccessible, and every regular cardinal strictly between κ\kappa and 2κ2^\kappa is the character of some uniform ultrafilter on κ\kappa.

Keywords

Cite

@article{arxiv.1907.11765,
  title  = {Ultrafilters on singular cardinals of uncountable cofinality},
  author = {James Cummings and Charles Morgan},
  journal= {arXiv preprint arXiv:1907.11765},
  year   = {2019}
}