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Related papers: Exact saturation in simple and NIP theories

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We introduce the class of unshreddable theories, which contains the simple and NIP theories, and prove that such theories have exactly saturated models in singular cardinals, satisfying certain set-theoretic hypotheses. We also give…

Logic · Mathematics 2021-04-19 Itay Kaplan , Nicholas Ramsey , Saharon Shelah

We study PC-exact saturation for stable and simple theories. Among other results, we show that PC-exact saturation characterizes the stability cardinals of size at least continuum of a countable stable theory and, additionally, that simple…

Logic · Mathematics 2022-05-10 Itay Kaplan , Nicholas Ramsey , Saharon Shelah

Saturation is (mu,kappa)-transferable in T if and only if there is an expansion T_1 of T with |T_1| = |T| such that if M is a mu-saturated model of T_1 and |M| \geq kappa then the reduct M|L(T) is kappa-saturated. We characterize theories…

Logic · Mathematics 2008-02-03 J. Baldwin , R. Grossberg , Saharon Shelah

We show that it is consistent relative to a huge cardinal that for all infinite cardinals $\kappa$, $\square_\kappa$ holds and there is a stationary $S \subseteq \kappa^+$ such that $\mathrm{NS}_{\kappa^+} \restriction S$ is…

Logic · Mathematics 2020-04-27 Monroe Eskew

We try to understand complete types over a somewhat saturated model of a complete first order theory which is dependent (previously called NIP), by "decomposition theorems for such types". Our thesis is that the picture of dependent theory…

Logic · Mathematics 2013-12-25 Saharon Shelah

Automated theorem provers (ATPs) can disprove conjectures by saturating a set of clauses, but the resulting saturated sets are opaque certificates. In the unit equational fragment, a saturated set can in fact be read as a convergent rewrite…

Logic in Computer Science · Computer Science 2026-02-19 Mikoláš Janota , Michael Rawson , Stephan Schulz

We investigate a notion called uniqueness in power kappa that is akin to categoricity in power kappa, but is based on the cardinality of the generating sets of models instead of on the cardinality of their universes. The notion is quite…

Logic · Mathematics 2016-09-06 Steven Givant , Saharon Shelah

Let K be an algebraically bounded structure and T be its theory. If T is model complete, then the theory of K endowed with a derivation, denoted by $T^{\delta}$, has a model completion. Additionally, we prove that if the theory T is…

Logic · Mathematics 2024-11-14 Fornasiero Antongiulio , Terzo Giuseppina

In this paper we prove a strong nonstructure theorem for kappa (T)-saturated models of a stable theory T with dop.

Logic · Mathematics 2009-09-25 Tapani Hyttinen , Saharon Shelah

We study one way in which stable phenomena can exist in an NIP theory. We start by defining a notion of 'pure instability' that we call 'distality' in which no such phenomenon occurs. O-minimal theories and the p-adics for example are…

Logic · Mathematics 2015-09-24 Pierre Simon

We give several characterizations of when a complete first-order theory $T$ is monadically NIP, i.e. when expansions of $T$ by arbitrary unary predicates do not have the independence property. The central characterization is a condition on…

Logic · Mathematics 2026-05-06 Samuel Braunfeld , Michael C. Laskowski

A relevant thesis is that for the family of complete first order theories with NIP (i.e. without the independence property) there is a substantial theory, like the family of stable (and the family of simple) first order theories. We examine…

Logic · Mathematics 2007-05-23 Saharon Shelah

We investigate the class of models of a general dependent theory. We continue math.LO/0702292 in particular investigating so called "decomposition of types"; thesis is that what holds for stable theory and for Th(Q,<) hold for dependent…

Logic · Mathematics 2012-02-28 Saharon Shelah

We apply the recently developed technology of cofinality spectrum problems to prove a range of theorems in model theory. First, we prove that any model of Peano arithmetic is $\lambda$-saturated iff it has cofinality $\geq \lambda$ and the…

Logic · Mathematics 2015-03-31 M. Malliaris , S. Shelah

We are proving the following: (1) If $\kap$ is a weakly inaccessible then $NS_\kap$ is not $\kap^+$-saturated. (2) If $\kap$ is a weakly inaccessible and $\tet <\kap$ is regular then $NS^\tet_\kap$ is not $\kap^+$-saturated. (3) If $\kap$…

Logic · Mathematics 2016-09-06 Moti Gitik , Saharon Shelah

We prove that for every simple theory $T$ (or even simple thick compact abstract theory) there is a (unique) compact abstract theory $T^\fP$ whose saturated models are the lovely pairs of $T$. Independence-theoretic results that were proved…

Logic · Mathematics 2009-02-05 Itaï Ben Yaacov

We continue our study of Sierpinski-type colourings. In contrast to the prequel paper, we focus here on colourings for ideals stratified by their completeness degree. In particular, improving upon Ulam's theorem and its extension by Hajnal,…

Logic · Mathematics 2023-12-19 Tanmay Inamdar , Assaf Rinot

Suppose that lambda is the successor of a singular cardinal mu whose cofinality is an uncountable cardinal kappa. We give a sufficient condition that the club filter of lambda concentrating on the points of cofinality kappa is not…

Logic · Mathematics 2008-02-03 Mirna Džamonja , Saharon Shelah

We give sufficient conditions for a predicate P in a complete theory T to be stably embedded: P with its induced 0-definable structure has "finite rank", P has NIP in T and P is 1-stably embedded. This generalizes recent work by Hasson and…

Logic · Mathematics 2010-01-05 Anand Pillay

We prove that some natural "outside" property is equivalent (for a first order class) to being stable. For a model, being resplendent is a strengthening of being kappa-saturated. Restricting ourselves to the case kappa > |T| for…

Logic · Mathematics 2022-10-18 Saharon Shelah
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