Closed Unbounded classes and the Haertig Quantifier Model
Logic
2019-03-08 v1
Abstract
We show that assuming modest large cardinals, there is a definable class of ordinals, closed and unbounded beneath every uncountable cardinal, so that for any closed and unbounded subclasses , and possess the same reals, satisfy the Generalised Continuum Hypothesis, and moreover are elementarily equivalent. The theory of such models is thus invariant under set forcing. They also all have a rich structure satisfying many of the usual combinatorial principles and a definable wellorder of the reals. One outcome is that we can characterize the inner model constructed using definability in the language augmented by the H\"artig quantifier when such a is itself .
Keywords
Cite
@article{arxiv.1903.02663,
title = {Closed Unbounded classes and the Haertig Quantifier Model},
author = {Philip Welch},
journal= {arXiv preprint arXiv:1903.02663},
year = {2019}
}