English

A Framework for Forcing Constructions at Successors of Singular Cardinals

Logic 2016-05-23 v3

Abstract

We describe a framework for proving consistency results about singular cardinals of arbitrary cofinality and their successors. This framework allows the construction of models in which the Singular Cardinals Hypothesis fails at a singular cardinal of uncountable cofinality, while its successor enjoys various combinatorial properties. As a sample application, we prove the consistency (relative to that of ZFC plus a supercompact cardinal) of there being a strong limit singular cardinal κ\kappa of uncountable cofinality where SCH fails and for which there is a collection of graphs on κ+\kappa^+ whose size is less than 2κ2^\kappa and such that any graph on κ+\kappa^+ embeds into one of the graphs in the collection.

Keywords

Cite

@article{arxiv.1403.6795,
  title  = {A Framework for Forcing Constructions at Successors of Singular Cardinals},
  author = {James Cummings and Mirna Džamonja and Menachem Magidor and Charles Morgan and Saharon Shelah},
  journal= {arXiv preprint arXiv:1403.6795},
  year   = {2016}
}

Comments

53 pages