We discuss how much the notion '\(\sigma\) has a model of size \(\aleph_\alpha\)' (where \(\sigma\) is a sentence of \(L_{\omega_1,\omega}\)) can depend on set theoretic properties. After some general remarks and examples, we will focus on the presentation of a complete sentence for which model-existence in \(\aleph_3\) is non-absolute modulo ZFCGCH.
Non-absoluteness of model existence for infinitary logic
06.10.2011 15:00 - 16:30
Organiser:
KGRC
Location:
SR 101, 2. St., Währinger Str. 25