English
Related papers

Related papers: Metric abstract elementary classes as accessible c…

200 papers

Quantitative algebras are $\Sigma$-algebras acting on metric spaces, where operations are nonexpanding. Mardare, Panangaden and Plotkin introduced 1-basic varieties as categories of quantitative algebras presented by quantitative equations.…

Category Theory · Mathematics 2026-02-06 J. Adámek , M. Dostál , J. Velebil

We use the framework of Abstract Elementary Classes ($\mathrm{AEC}$s) to introduce a new Construction Principle $\mathrm{CP}(\mathbf{K},\ast)$, which generalises the Construction Principle of Eklof, Mekler and Shelah and allows for many…

Logic · Mathematics 2026-04-29 Tapani Hyttinen , Gianluca Paolini , Davide Emilio Quadrellaro

In my PhD thesis a version of Shelah's Presentation Theorem in the setting of Metric Abstract Elementary Classes was proved, where we claimed that the new function symbols are not necessarily uniformly continuous. In this paper we provide a…

Logic · Mathematics 2015-04-22 Pedro Zambrano

A locally coherent exact category is a finitely accessible additive category endowed with an exact structure in which the admissible short exact sequences are the directed colimits of admissible short exact sequences of finitely presentable…

Category Theory · Mathematics 2024-07-31 Leonid Positselski

Motivated by the analysis and geometry of metric-measure structures in infinite dimensions, we study the category of extended metric-topological spaces, along with many of its distinguished subcategories (such as the one of compact spaces).…

Category Theory · Mathematics 2026-01-13 Enrico Pasqualetto , Timo Schultz , Janne Taipalus

This paper contains results from two areas -- formal theory of Kan extensions and concrete categories. The contribution to the former topic is based on the extension of the concept of Kan extension to the cones and we prove that limiting…

Category Theory · Mathematics 2011-04-19 Jan Pavlík

Metric algebras are metric variants of $\Sigma$-algebras. They are first introduced in the field of universal algebra to deal with algebras equipped with metric structures such as normed vector spaces. Recently a similar notion of…

Logic in Computer Science · Computer Science 2016-12-27 Wataru Hino

Part I: We would like to generalize imaginary elements, weight of ${\rm ortp}(a,M,N),{\mathbf P}$-weight, ${\mathbf P}$-simple types, etc. from [Sh:c, Ch.III,V,\S4] to the context of good frames. This requires allowing the vocabulary to…

Logic · Mathematics 2023-05-04 Saharon Shelah

In this work we present some general categorial ideas on Abstract Elementary Classes (AECs) %\cite{She}, inspired by the totality of AECs of the form $(Mod(T), \preceq)$, for a first-order theory T: (i) we define a natural notion of…

Logic · Mathematics 2014-05-20 Hugo Luiz Mariano , Andrés Villaveces , Pedro Hernan Zambrano

Essential $\aleph_0$-categoricity; i.e., $\aleph_0$-categoricity in some full countable language, is shown to be a robust notion for strongly minimal compact complex manifolds. Characterisations of triviality and essential…

Logic · Mathematics 2010-07-06 Rahim Moosa , Anand Pillay

Metric approximate categories, or metagories, for short, are metrically enriched graphs. Their structure assigns to every directed triangle in the graph a value which may be interpreted as the area of the triangle; alternatively, as the…

Category Theory · Mathematics 2019-04-02 Walter Tholen , Jiyu Wang

We give a purely category-theoretic proof of the result of Makkai and Par\'e saying that the category $\bf Lin$ of linearly ordered sets and order preserving injective mappings is a minimal finitely accessible category. We also discuss the…

Category Theory · Mathematics 2022-02-08 Jiří Rosický

We deal with stability theory for ``reasonable'' non-elementary classes without any remanents of compactness (like: above Hanf number or definable by L_{omega_1, omega}).

Logic · Mathematics 2007-08-15 Saharon Shelah

We study the $2$-categories BIon, of (generalized) bounded ionads, and $\text{Acc}_\omega$, of accessible categories with directed colimits, as an abstract framework to approach formal model theory. We relate them to topoi and (lex)…

Category Theory · Mathematics 2025-08-05 Ivan Di Liberti

Compact metric spaces form an important class of metric spaces, but the category that they define lacks many important properties such as completeness and cocompleteness. In recent studies of "metric domain theory" and Stone-type dualities,…

Category Theory · Mathematics 2025-01-15 Marco Abbadini , Dirk Hofmann

Metric spaces are a fundamental component of mathematics and have a paramount importance as a framework for measuring distance. They can be found in many different branches of mathematics, such as analysis and topology. This paper offers an…

General Topology · Mathematics 2025-10-30 Ismail Gemaledin , Iusuf Gemaledin

The paper is devoted to a categorical study of the category of probabilistic metric spaces. The study is based on an isomorphic description of the category of probabilistic metric spaces. The isomorphic description was obtained in [3] and…

General Topology · Mathematics 2026-04-02 Eva Colebunders , Robert Lowen

We develop foundations for oriented category theory, an extension of $(\infty,\infty)$-category theory obtained by systematic usage of the Gray tensor product, in order to study lax phenomena in higher category theory. As categorical…

Algebraic Topology · Mathematics 2025-10-14 David Gepner , Hadrian Heine

The importance of accessible categories has been widely recognized; they can be described as those freely generated in some precise sense by a small set of objects and, because of that, satisfy many good properties. More specifically…

Category Theory · Mathematics 2022-05-31 Stephen Lack , Giacomo Tendas

In this paper we examine the task set forth by Shelah and Villaveces in \cite{ShVi} of proving the uniqueness of limit models of cardinality $\mu$ in $\lambda$-categorical abstract elementary classes with no maximal models, where $\lambda$…

Logic · Mathematics 2016-12-02 Monica M. VanDieren