324 citations · 1.7k across the 753 of their papers we have counts for
9 papers · 1 filter
Black Boxes
Saharon Shelah
We shall deal comprehensively with Black Boxes, the intention being that provably in ZFC we have a sequence of guesses of extra structure on small subsets, where the guesses are pa…
Unstable classes of metric structures
Saharon Shelah, Alexander Usvyatsov
We prove a strong non-structure theorem for a class of metric structures with an unstable pair of formulae. As a consequence, we show that weak categoricity (that is, categoricity…
Categoricity and solvability of A.E.C., quite highly
Saharon Shelah
We investigate in ZFC what can be the family of large enough cardinals mu in which an a.e.c. K is categorical or even just solvable. We show that for not few cardinals lambda<mu th…
Non-structure in lambda^{++} using instances of WGCH
Saharon Shelah
We try to redo, improve and continue the non-structure parts in some works on a.e.c., which uses weak diamond, in lambda^+ and lambda^{++} getting better and more results and do wh…
Models of expansions of N with no end extensions
Saharon Shelah
We deal with models of Peano arithmetic (specifically with a question of Ali Enayat). The methods are from creature forcing. We find an expansion of N such that its theory has mode…
Partial choice functions for families of finite sets
Eric J. Hall, Saharon Shelah
Let m>2 be an integer. We show that ZF + "For every integer n, Every countable family of non-empty sets of cardinality at most n has an infinite partial choice function" is not str…