324 citations · 1.7k across the 753 of their papers we have counts for
22 papers · 2 filters
Ultrafilter extensions do not preserve elementary equivalence
Denis I. Saveliev, Saharon Shelah
We show that there exist models and such that elementarily embeds into but their ultrafilter extensions $β(\mathcal M_1)…
Automorphism Groups of Countable Stable Structures
Gianluca Paolini, Saharon Shelah
For every countable structure we construct an -stable countable structure such that and are topologically isomorphic. This shows that it is impo…
An extendible model with a rigid elementary extension
Paul B. Larson, Saharon Shelah
A countable structure is said to be extendible if it has the same Scott sentence as some uncountable structure. Rigid structures are not extendible. We give an example of an extend…
Polish Topologies for Graph Products of Groups
Gianluca Paolini, Saharon Shelah
We give strong necessary conditions on the admissibility of a Polish group topology for an arbitrary graph product of groups , and use them to give a characterization mo…
Infinite monochromatic sumsets for colourings of the reals
Péter Komjáth, Imre Leader, Paul A. Russell +3
N. Hindman, I. Leader and D. Strauss proved that it is consistent that there is a finite colouring of so that no infinite sumset is monochromatic…
On and the Juhasz-Kunen question
Mohammad Golshani, Saharon Shelah
We generalize the combinatorial principles and introduced by various authors, and prove some of their properties and connections between them. We also…