A cardinal preserving extension making the set of points of countableVcofinality nonstationary

✍ Scribed by Moti Gitik; Itay Neeman; Dima Sinapova

• Publisher: Springer
• Year: 2007
• Tongue: English
• Weight: 163 KB
• Volume: 46
• Category: Article
• ISSN: 0933-5846
• DOI: 10.1007/s00153-007-0048-0

✦ Synopsis

Assuming large cardinals we produce a forcing extension of V which preserves cardinals, does not add reals, and makes the set of points of countable V cofinality in κ+ nonstationary. Continuing to force further, we obtain an extension in which the set of points of countable V cofinality in ν is nonstationary for every regular ν ≥ κ+. Finally we show that our large cardinal assumption is optimal.