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Related papers: Pre-adjunctions and the Ramsey property

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The structural Ramsey theory is a field on the boundary of combinatorics and model theory with deep connections to topological dynamics. Most of the known Ramsey classes in finite binary symmetric relational language can be shown to be…

Combinatorics · Mathematics 2019-08-13 Matěj Konečný

In this paper we study a very general finite Ramsey theorem, where both the sets being colored and the homogeneous set must satisfy some largeness notion. For the homogeneous set this has already been done using the notion of…

Logic · Mathematics 2026-03-03 Alberto Marcone , Antonio Montalbán , Andrea Volpi

An n-vertex graph is called C-Ramsey if it has no clique or independent set of size C log n. All known constructions of Ramsey graphs involve randomness in an essential way, and there is an ongoing line of research towards showing that in…

Combinatorics · Mathematics 2021-09-08 Matthew Kwan , Benny Sudakov

We extend the Kechris--Pestov--Todor\v{c}evi\'c correspondence to weak Fra\"{\i}ss\'{e} categories and automorphism groups of generic objects. The new ingredient is the weak Ramsey property. We demonstrate the theory on several examples…

Logic · Mathematics 2024-11-20 Adam Bartoš , Tristan Bice , Keegan Dasilva Barbosa , Wiesław Kubiś

We prove a sharp structural result concerning finite colorings of pairs in well-founded trees.

Combinatorics · Mathematics 2019-05-17 R. M. Causey , C. Doebele

We discuss the externally definable Ramsey property, a weakening of the Ramsey property for ultrahomogeneous structures, where the only colourings considered are those that are externally definable: that is, definable with parameters in an…

Logic · Mathematics 2025-10-20 Nadav Meir , Rob Sullivan

We prove a new characterization of the Ramsey property of categories in terms of a generalized form of K\H{o}nig's tree lemma. Afterwards, we discuss its applications to structural Ramsey theory. In particular, we provide a new proof of the…

Combinatorics · Mathematics 2025-08-18 Maximilian Hadek

In this short note we confirm the deep structural correspondence between the complexity of a countable scattered chain (= strict linear order) and its big Ramsey combinatorics: we show that a countable scattered chain has finite big Ramsey…

Logic · Mathematics 2023-07-25 Keegan Dasilva Barbosa , Dragan Mašulović , Rajko Nenadov

Motivated by quite recent research involving the relationship between the dimension of a poset and graph-theoretic properties of its cover graph, we show that for every $d\geq 1$, if $P$ is a poset and the dimension of a subposet $B$ of $P$…

Combinatorics · Mathematics 2018-12-11 William T. Trotter , Bartosz Walczak , Ruidong Wang

In this paper we study structural properties of residuated lattices that are idempotent as monoids. We provide descriptions of the totally ordered members of this class and obtain counting theorems for the number of finite algebras in…

Logic · Mathematics 2020-04-22 José Gil-Férez , Peter Jipsen , George Metcalfe

We prove a new, efficient version of the hypergraph container theorems that is suited for hypergraphs with large uniformities. The main novelty is a refined approach to constructing containers that employs simple ideas from high-dimensional…

Combinatorics · Mathematics 2020-12-11 József Balogh , Wojciech Samotij

We further develop the theory of layered semigroups, as introduced by Farah, Hindman and McLeod, providing a general framework to prove Ramsey statements about such a semigroup $S$. By nonstandard and topological arguments, we show Ramsey…

Combinatorics · Mathematics 2021-04-26 Jordan Mitchell Barrett

A class of structures is said to have the homomorphism-preservation property just in case every first-order formula that is preserved by homomorphisms on this class is equivalent to an existential-positive formula. It is known by a result…

Logic in Computer Science · Computer Science 2009-03-08 Anuj Dawar

We extend the hierarchy of finite-dimensional Ellentuck spaces to infinite dimensions. Using uniform barriers $B$ on $\omega$ as the prototype structures, we construct a class of continuum many topological Ramsey spaces $\mathcal{E}_B$…

Logic · Mathematics 2015-09-22 Natasha Dobrinen

Ramsey algebras are algebras that induce Ramsey spaces, which are generalizations of the Ellentuck space and Milliken's space. Previous work suggests a possible local version of Ramsey algebras induced by infinite sequences. Hence, we…

Logic · Mathematics 2017-04-13 Wen Chean Teh , Zu Yao Teoh

In this series of papers, we advance Ramsey theory of colorings over partitions. In this part, a correspondence between anti-Ramsey properties of partitions and chain conditions of the natural forcing notions that homogenize colorings over…

Logic · Mathematics 2022-04-19 Menachem Kojman , Assaf Rinot , Juris Steprans

The recently introduced model of representations has been defined and motivated somewhat ex-nihilo. In this document, I will show that representations are related to a more ''classical'' model through a 2-adjunction. The target model is…

Logic in Computer Science · Computer Science 2026-04-21 Paul Brunet

In this note we consider a Ramsey type result for partially ordered sets. In particular, we give an alternative short proof of a theorem for a posets with multiple linear extensions recently obtained by Solecki and Zhao.

Combinatorics · Mathematics 2016-08-19 Andrii Arman , Vojtěch Rödl

Classes with bounded rankwidth are MSO-transductions of trees and classes with bounded linear rankwidth are MSO-transductions of paths -- a result that shows a strong link between the properties of these graph classes considered from the…

Logic in Computer Science · Computer Science 2019-09-05 Jaroslav Nesetril , Patrice Ossona de Mendez , Roman Rabinovich , Sebastian Siebertz

We generalize the notion of relational precompact expansions of Fra\"iss\'e classes via functorial means, inspired by the technique outlined by Laflamme, Nguyen Van Th\'e and Sauer in their paper Partition properties of the dense local…

Combinatorics · Mathematics 2020-02-28 Keegan Dasilva Barbosa
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