A consistency result on weak reflection
Logic
2009-09-25 v1
Abstract
In this paper we study the notion of strong non-reflection, and its contrapositive weak reflection. We say theta strongly non-reflects at lambda iff there is a function F: theta ---> lambda such that for all alpha < theta with cf(alpha)= lambda there is C club in alpha such that F restriction C is strictly increasing. We prove that it is consistent to have a cardinal theta such that strong non-reflection and weak reflection each hold on an unbounded set of cardinals less than theta .
Keywords
Cite
@article{arxiv.math/9504221,
title = {A consistency result on weak reflection},
author = {James Cummings and Mirna Džamonja and Saharon Shelah},
journal= {arXiv preprint arXiv:math/9504221},
year = {2009}
}