324 citations · 1.7k across the 753 of their papers we have counts for
32 papers · 2 filters
Superdestructibility: a dual to Laver indestructibility
Joel David Hamkins, Saharon Shelah
After small forcing, any < kappa-closed forcing will destroy the supercompactness, even the strong compactness, of kappa .
Club does not imply the existence of a Suslin tree
Mirna Džamonja, Saharon Shelah
We prove that club does not imply the existence of a Suslin tree, so answering a question of I. Juhasz.
There may be no nowhere dense ultrafilter
Saharon Shelah
We show the consistency of ZFC +''there is no NWD-ultrafilter on omega'', which means: for every non principle ultrafilter D on the set of natural numbers, there is a function f fr…
Subalgebras of Cohen algebras need not be Cohen
Sabine Koppelberg, Saharon Shelah
We give an example of a regular and complete subalgebra of a Cohen algebra which is not Cohen.
Further cardinal arithmetic
Saharon Shelah
We continue the investigations in the author's book on cardinal arithmetic, assuming some knowledge of it. We deal with the cofinality of (S_{<= aleph_0}(kappa), subseteq) for kapp…
Ideals without ccc
Marek Balcerzak, Andrzej Rosłanowski, Saharon Shelah
Let I be an ideal of subsets of a Polish space X, containing all singletons and possessing a Borel basis. Assuming that I does not satisfy ccc, we consider the following conditions…