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Related papers: Externally definable sets and dependent pairs

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We discuss measures, invariant measures on definable groups, and genericity, often in an NIP (failure of the independence property) environment. We complete the proof of the third author's conjectures relating definably compact groups $G$…

Logic · Mathematics 2007-05-23 Ehud Hrushovski , Ya'acov Peterzil , Anand Pillay

The stability problem of a class of nonlinear switched systems defined on compact sets with state-dependent switching is considered. Instead of the Caratheodory solutions, the general Filippov solutions are studied. This encapsulates…

Optimization and Control · Mathematics 2017-07-31 Mohamadreza Ahmadi , Hamed Mojallali , Rafael Wisniewski

We continue our investigation =of Shelah's interpretability orders $\trianglelefteq^*_\kappa$ as well as the new orders $\trianglelefteq^\times_\kappa$. In particular, we give streamlined proofs of the existence of minimal unstable,…

Logic · Mathematics 2018-11-14 Douglas Ulrich

I develop in depth the machinery of $(\mathcal L, n)$-models originally introduced by Shelah and, independently in a slightly different form by Kripke. This machinery allows fairly routine constructions of true but unprovable sentences in…

Logic · Mathematics 2021-08-12 Corey Bacal Switzer

We investigate bounds in Ramsey's theorem for relations definable in NIP structures. Applying model-theoretic methods to finitary combinatorics, we generalize a theorem of Bukh and Matousek [B. Bukh, J. Matou\v{s}ek.…

Logic · Mathematics 2021-01-27 Artem Chernikov , Sergei Starchenko , Margaret E. M. Thomas

We consider profinite groups as 2-sorted first order structures, with a group sort, and a second sort which acts as an index set for a uniformly definable basis of neighbourhoods of the identity. It is shown that if the basis consists of…

Logic · Mathematics 2017-05-17 Dugald Macpherson , Katrin Tent

The task of natural language inference (NLI) asks whether a given premise (expressed in NL) entails a given NL hypothesis. NLI benchmarks contain human ratings of entailment, but the meaning relationships driving these ratings are not…

Computation and Language · Computer Science 2023-09-06 Juri Opitz , Shira Wein , Julius Steen , Anette Frank , Nathan Schneider

A first-order theory has the Schroder-Bernstein property if any two of its models that are elementarily bi-embeddable are isomorphic. We prove that if a countable theory T has the Schroder-Bernstein property then it is classifiable (it is…

Logic · Mathematics 2007-05-23 John Goodrick

The following natural question arises from Shalom's innovational work (1999, Publ. IHES): "Can we establish an intrinsic criterion to synthesize relative fixed point properties into the whole fixed point property without assuming Bounded…

Group Theory · Mathematics 2016-11-16 Masato Mimura

There is much more known about the family of superstable theories when compared to stable theories. This calls for a search of an analogous "super-dependent" characterization in the context of dependent theories. This problem has been…

Logic · Mathematics 2013-03-15 Moran Cohen , Saharon Shelah

A theoretical development is carried to establish fundamental results about rank-initial embeddings and automorphisms of countable non-standard models of set theory, with a keen eye for their sets of fixed points. These results are then…

Logic · Mathematics 2021-06-17 Paul K. Gorbow

We prove that the expressive power of first-order logic with team semantics plus contradictory negation does not rise beyond that of first-order logic (with respect to sentences), and that the totality atoms of arity k +1 are not definable…

Logic · Mathematics 2014-03-18 Pietro Galliani

We observe that a simple condition suffices to describes non-forking independence over models in a stable theory. Under mild assumptions, this description can be extended to non-forking independence over algebraically closed subsets,…

Logic · Mathematics 2024-10-15 Amador Martin-Pizarro

In this paper, we prove some new thickness theorems with partial derivatives. We give some applications. First, we give a simple criterion that can judge whether two scaled Cantor sets have non-empty intersection. Second, we prove under…

Dynamical Systems · Mathematics 2022-12-02 Kan Jiang

We introduce the definability strength of combinatorial principles. In terms of definability strength, a combinatorial principle is strong if solving a corresponding combinatorial problem could help in simplifying the definition of a…

Logic · Mathematics 2017-02-28 Wei Wang

We study compressible types in the context of (local and global) NIP. By extending a result in machine learning theory (the existence of a bound on the recursive teaching dimension), we prove density of compressible types. Using this, we…

Logic · Mathematics 2026-04-02 Martin Bays , Itay Kaplan , Pierre Simon

We generalise the main theorems from the paper "The Borel cardinality of Lascar strong types" by I. Kaplan, B. Miller and P. Simon to a wider class of bounded invariant equivalence relations. We apply them to describe relationships between…

Logic · Mathematics 2016-03-14 Krzysztof Krupiński , Tomasz Rzepecki

We introduce the notion of dependence, as a property of a Keisler measure, and generalize several results of [HPS13] on generically stable measures (in $NIP$ theories) to arbitrary theories. Among other things, we show that this notion is…

Logic · Mathematics 2025-06-09 Karim Khanaki

A note connecting arguments scattered in the extant literature proving that, in any o-minimal expansion of the real field, a definable family of sets has the property that the set of parameters corresponding to finite-volume fibers is…

Logic · Mathematics 2025-08-14 L. C. Brown

The usual definition of the set of constructible reals is $\Sigma ^1_2$. This set can have a simpler definition if, for example, it is countable or if every real is constructible. H. Friedman asked if the set of constructible reals can be…

Logic · Mathematics 2016-09-06 Boban Velickovic , W. Hugh Woodin
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