Using iterated ultrapowers to build many atomic models of size aleph1
Chris Laskowski, University of Maryland
Abstract:
We describe how the method of iterated ultrapowers can be used to construct many disparate atomic models of size aleph1. This technique can be distilled into a general Transfer theorem, which we state and prove. This has the amusing corollary that in some cases, one can use a ccc forcing notion to give a ZFC proof of the existence of 2^\aleph1 pairwise non-isomorphic atomic models. This is joint work with John Baldwin and Saharon Shelah.