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Related papers: Forking and superstability in tame AECs

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We present a setting for the study of torsion theories in general categories. The idea is to associate, with any pair ($\mathcal T$, $\mathcal F$) of full replete subcategories in a category $\mathcal C$, the corresponding full subcategory…

Category Theory · Mathematics 2022-01-04 Alberto Facchini , Carmelo Finocchiaro , Marino Gran

In classification, it is usual to observe that models trained on a given set of classes can generalize to previously unseen ones, suggesting the ability to learn beyond the initial task. This ability is often leveraged in the context of…

Machine Learning · Computer Science 2024-03-07 Raphael Baena , Lucas Drumetz , Vincent Gripon

We study $\varepsilon$-stability in continuous logic. We first consider stability in a model, where we obtain a definability of types result with a better approximation than that in the literature. We also prove forking symmetry for…

Logic · Mathematics 2024-11-08 Nicolas Chavarria

We seek to create tools for a model-theoretic analysis of types in algebraically closed valued fields (ACVF). We give evidence to show that a notion of 'domination by stable part' plays a key role. In Part A, we develop a general theory of…

Logic · Mathematics 2007-05-23 Deirdre Haskell , Ehud Hrushovski , Dugald Macpherson

We show that many nice properties of a theory $T$ follow from the corresponding properties of its reducts to finite subsignatures. If $\{ T_i \}_{i \in I}$ is a directed family of conservative expansions of first-order theories and each…

Logic · Mathematics 2015-08-26 Alice Medvedev

Assuming the existence of a strong cardinal and a measurable cardinal above it, we construct a model of $ZFC$ in which for every singular cardinal $\delta$, $\delta$ is strong limit, $2^\delta=\delta^{+3}$ and the tree property at…

Logic · Mathematics 2018-05-22 Mohammad Golshani

For every algebraically closed field $\boldsymbol k$ of characteristic different from $2$, we prove the following: (1) Generic finite dimensional (not necessarily associative) $\boldsymbol k$-algebras of a fixed dimension, considered up to…

Algebraic Geometry · Mathematics 2015-01-20 Vladimir L. Popov

We show that the ample degree of a stable theory with trivial forking is preserved when we consider the corresponding theory of belles paires, if it exists. This result also applies to the theory of $H$-structures of a trivial theory of…

Logic · Mathematics 2019-09-18 Enrique Casanovas , Amador Martin-Pizarro , Daniel Palacin

We bring forward a logical system of transition algebras that enhances many-sorted first-order logic using features from dynamic logics. The sentences we consider include compositions, unions, and transitive closures of transition…

Logic in Computer Science · Computer Science 2024-04-26 Hashimoto Go , Daniel Găină , Ionuţ Ţuţu

Whenever x is a tame cardinal invariant and ZFC+large cardinals proves that x=aleph one implies WCG then ZFC+large cardinals proves that x=aleph one implies b=aleph one, and b=aleph one implies WCG. Here WCG is a certain prediction…

Logic · Mathematics 2007-05-23 Jindrich Zapletal

We work with a pre-$\lambda$-frame, which is an abstract elementary class (AEC) endowed with a collection of basic types and a non-forking relation satisfying certain natural properties with respect to models of cardinality $\lambda$. We…

Logic · Mathematics 2018-11-02 Ari Meir Brodsky , Adi Jarden

We identify a premouse inner model $L[\mathbb{E}]$, such that for any coarsely iterable background universe $R$ modelling $\mathrm{ZFC}$, $L[\mathbb{E}]^R$ is a proper class premouse of $R$ inheriting all strong and Woodin cardinals from…

Logic · Mathematics 2020-04-28 Farmer Schlutzenberg

We study methods to obtain the consistency of forcing axioms, and particularly higher forcing axioms. We first force over a model with a supercompact cardinal $\theta>\kappa$ to get the consistency of the forcing axiom for $\kappa$-strongly…

Logic · Mathematics 2024-03-19 David Asperó , Sean Cox , Asaf Karagila , Christoph Weiss

Based on Crapo's theory of one point extensions of combinatorial geometries, we find various classes of geometric lattices that behave very well from the point of view of stability theory. One of them, $(\mathbf{K}^3, \preccurlyeq)$, is…

Logic · Mathematics 2017-10-10 Tapani Hyttinen , Gianluca Paolini

We rewrite classical topological definitions using the category-theoretic notation of arrows and are led to concise reformulations in terms of simplicial categories and orthogonality of morphisms, which we hope might be of use in the…

Category Theory · Mathematics 2018-07-19 Misha Gavrilovich , Konstantin Pimenov

We show that various tameness assertions about abstract elementary classes imply the existence of large cardinals under mild cardinal arithmetic assumptions.

Logic · Mathematics 2016-10-20 Will Boney , Spencer Unger

We introduce a generalisation of Condition (K) to finitely separated graphs and show that it is equivalent to essential freeness of the associated partial action as well as the exchange property of any of the associated tame algebras. As a…

Operator Algebras · Mathematics 2017-05-15 Matias Lolk

Several variations on the definition of a Formal Topology exist in the literature. They differ on how they express convergence, the formal property corresponding to the fact that open subsets are closed under finite intersections. We…

Logic · Mathematics 2012-11-06 Francesco Ciraulo , Maria Emilia Maietti , Giovanni Sambin

When we investigate a type system, it is helpful if we can establish the well-foundedness of types or terms with respect to a certain hierarchy, and the Extended Calculus of Constructions (called $ECC$, defined and studied comprehensively…

Logic in Computer Science · Computer Science 2021-05-12 Eitetsu Ken , Masaki Natori , Kenji Tojo , Kazuki Watanabe

In [Sh E46], Shelah obtained a non-forking relation for an AEC, (K,\preceq), with LST-number at most \lambda, which is categorical in \lambda and \lambda^+ and has less than 2^{\lambda^+} models of cardinality \lambda^{++}, but at least…

Logic · Mathematics 2011-05-19 Adi Jarden , Saharon Shelah