3 papers
math.LO2000
On properties of theories which preclude the existence of universal models
Mirna Džamonja, Saharon Shelah
In this paper we investigate some properties of first order theories which prevent them from having universal models under certain cardinal arithmetic assumptions. Our results give…
math.LO1999
Strongly meager and strong measure zero sets
Tomek Bartoszynski, Saharon Shelah
We show that the following are consistent with ZFC: 1. Strongly meager sets form an ideal with the same additivity as the ideal of meager sets. 2. There exists a strong measure zer…
math.LO1999
On absolutely divergent series
Sakae Fuchino, Heike Mildenberger, Saharon Shelah +1
We show that in the aleph_2-stage countable support iteration of Mathias forcing over a model of CH the complete Boolean algebra generated by absolutely divergent series under even…