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Related papers: Extreme types and extremal models

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We show that constructible models of arbitrary complete continuous first-order theories are unique up to isomorphism.

Logic · Mathematics 2025-01-07 James E. Hanson

We consider varieties generated by finite closure algebras whose canonical relations have two levels, and whose restriction to a level is an "extremal" relation, i.e. the identity or the universal relation. The corresponding logics have…

Logic · Mathematics 2023-09-21 Ivo Düntsch , Wojciech Dzik

We develop some basic results about full amalgamation classes with intrinsic trascendentals. These classes have generics whose models may have finite subsets whose intrinsic closure is not contained in its algebraic closure. We will show…

Logic · Mathematics 2015-12-15 Justin Brody

Inspired in the theorem of Krein-Milamn, we investigate the existence of extreme points in compact convex subsets of asymmetric normed spaces. We focus our attention in the finite dimensional case, giving a geometric description of all…

Functional Analysis · Mathematics 2014-04-03 Natalia Jonard-Pérez , Enrique A. Sánchez-Pérez

We characterize the smallest finite spaces with the same homotopy groups of the spheres. Similarly, we describe the minimal finite models of any finite graph. We also develop new combinatorial techniques based on finite spaces to study…

Algebraic Topology · Mathematics 2007-05-23 Jonathan Ariel Barmak , Elias Gabriel Minian

In many instances in first order logic or computable algebra, classical theorems show that many problems are undecidable for general structures, but become decidable if some rigidity is imposed on the structure. For example, the set of…

Discrete Mathematics · Computer Science 2017-08-08 Emmanuel Jeandel

We revisit the known problem whether each compact topology is contained in a maximal compact topology and collect some partial answers to this question. For instance we show that each compact topology is contained in a compact topology in…

General Topology · Mathematics 2007-05-23 Hans-Peter A. Künzi , Dominic van der Zypen

For a category $\mathcal E$ with finite limits and well-behaved countable coproducts, we construct a model structure, called the effective model structure, on the category of simplicial objects in $\mathcal E$, generalising the Kan--Quillen…

Category Theory · Mathematics 2022-11-11 Nicola Gambino , Simon Henry , Christian Sattler , Karol Szumiło

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

The compactness theorem for a logic states, roughly, that the satisfiability of a set of well-formed formulas can be determined from the satisfiability of its finite subsets, and vice versa. Usually, proofs of this theorem depend on the…

Logic · Mathematics 2025-07-04 Sayantan Roy , Sankha S. Basu , Mihir K. Chakraborty

We establish the following model-theoretic characterization: profinite $L$-structures, the cofiltered limits of finite $L$-structures,are retracts of ultraproducts of finite $L$-structures. As a consequence, any elementary class of…

Logic · Mathematics 2007-05-23 Hugo Luiz Mariano

We study the extremes for a class of a symmetric stable random fields with long range dependence. We prove functional extremal theorems both in the space of sup measures and in the space of cadlag functions of several variables. The limits…

Probability · Mathematics 2018-10-17 Zaoli Chen , Gennady Samorodnitsky

We investigate the extent to which Linear Temporal Logic (LTL) formulas can be uniquely characterized by a finite set of labeled examples. We consider different types of examples, ranging from finite words to transfinite words, as well as…

Logic in Computer Science · Computer Science 2026-04-27 Balder ten Cate , Dana Fisman , Roi Ohayon , Patrik Sestic

We begin the study of categorical logic for continuous model theory. In particular, we 1. introduce the notions of metric logical categories and functors as categorical equivalents of a metric theory and interpretations, 2. prove a…

Logic · Mathematics 2016-07-12 Jean-Martin Albert , Bradd Hart

We study the uniqueness of optimal solutions to extremal graph theory problems. Lovasz conjectured that every finite feasible set of subgraph density constraints can be extended further by a finite set of density constraints so that the…

Combinatorics · Mathematics 2020-08-26 Andrzej Grzesik , Daniel Král' , László Miklós Lovász

For tame arbitrary-length toral, also called positive regular, supercuspidal representations of a simply connected and semisimple $p$-adic group $G$, constructed as per Adler-Yu, we determine which components of their restriction to a…

Representation Theory · Mathematics 2021-02-01 Peter Latham , Monica Nevins

We investigate when the categories of all rational $A$-modules and of finite dimensional rational modules are closed under extensions inside the category of $C^*$-modules, where $C^*$ is the cofinite topological completion of $A$. We give a…

Category Theory · Mathematics 2011-10-13 Miodrag C. Iovanov

We examine the class of languages that can be defined entirely in terms of provability in an extension of the sorted type theory (Ty_n) by embedding the logic of phonologies, without introduction of special types for syntactic entities.…

Computation and Language · Computer Science 2011-02-28 Victor Gluzberg

The aim of this paper is introduce and initiate the study of extremally $T_1$-spaces, i.e., the spaces where all hereditarily compact $C_2$-subspaces are closed. A $C_2$-space is a space whose nowhere dense sets are finite.

General Topology · Mathematics 2007-05-23 Julian Dontchev , Maximilian Ganster , Laszlo Zsilinszky

Let $\Lambda$ be a finite dimensional algebra over an algebraically closed field. We exhibit slices of the representation theory of $\Lambda$ that are always classifiable in stringent geometric terms. Namely, we prove that, for any…

Representation Theory · Mathematics 2014-07-11 H. Derksen , B. Huisgen-Zimmermann , J. Weyman