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Related papers: On Metric Ramsey-type Dichotomies

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Metric Ramsey theory is concerned with finding large well-structured subsets of more complex metric spaces. For finite metric spaces this problem was first studies by Bourgain, Figiel and Milman \cite{bfm}, and studied further in depth by…

Data Structures and Algorithms · Computer Science 2021-04-09 Yair Bartal

We give a short survey of problems and results on (1) diameter graphs and hypergraphs, and (2) geometric Ramsey theory. We also make some modest contributions to both areas. Extending a well known theorem of Kahn and Kalai which disproved…

Combinatorics · Mathematics 2020-03-24 Peter Frankl , János Pach , Christian Reiher , Vojtěch Rödl

Ramsey theory is a central and active branch of combinatorics. Although Ramsey numbers for graphs have been extensively investigated since Ramsey's work in the 1930s, there is still an exponential gap between the best known lower and upper…

Combinatorics · Mathematics 2025-01-03 António Girão , Gal Kronenberg , Alex Scott

A major line of research is discovering Ramsey-type theorems, which are results of the following form: given a graph parameter $\rho$, every graph $G$ with sufficiently large $\rho(G)$ contains a `well-structured' induced subgraph $H$ with…

Combinatorics · Mathematics 2018-08-15 Ilkyoo Choi , Michitaka Furuya , Ringi Kim , Boram Park

Automatic structures are infinite structures that are finitely represented by synchronized finite-state automata. This paper concerns specifically automatic structures over finite words and trees (ranked/unranked). We investigate the…

Logic in Computer Science · Computer Science 2023-02-14 Pascal Bergsträßer , Moses Ganardi , Anthony W. Lin , Georg Zetzsche

We classify a sharp phase transition threshold for Friedman's finite adjacent Ramsey theorem. We extend the method for showing this result to two previously known classifications involving Ramsey theorem variants: the Paris--Harrington…

Logic · Mathematics 2016-06-08 Florian Pelupessy

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

This paper investigates quasi-isometries between graphs with variable edge lengths. A quasi-isometry is a mapping between metric spaces that approximately preserves distances, allowing for a bounded amount of additive and multiplicative…

Combinatorics · Mathematics 2025-03-11 James Davies , Meike Hatzel , Robert Hickingbotham

Ramsey-good graphs are graphs that contain neither a clique of size $s$ nor an independent set of size $t$. We study doubly saturated Ramsey-good graphs, defined as Ramsey-good graphs in which the addition or removal of any edge necessarily…

Combinatorics · Mathematics 2026-04-24 Benjamin Przybocki , John Mackey , Marijn J. H. Heule , Bernardo Subercaseaux

Ramsey theory enables re-shaping of the basic ideas of quantum mechanics. Quantum observables represented by linear Hermitian operators are seen as the vertices of a graph. Relations of commutation define the coloring of edges linking the…

Mathematical Physics · Physics 2024-11-13 Edward Bormashenko , Nir Shvalb

We develop a bifurcation theory for infinite dimensional systems satisfying abstract hypotheses that are tailored for applications to mean field coupled chaotic maps. Our abstract theory can be applied to many cases, from globally coupled…

Dynamical Systems · Mathematics 2025-01-14 Wael Bahsoun , Carlangelo Liverani

Ramsey theory looks for regularities in large objects. Model theory studies algebraic structures as models of theories. The structural Ramsey theory combines these two fields and is concerned with Ramsey-type questions about certain…

Combinatorics · Mathematics 2018-05-22 Matěj Konečný

One of the consequences of the Compactness Principle in structural Ramsey theory is that the small Ramsey degrees cannot exceed the corresponding big Ramsey degrees, thereby justifying the choice of adjectives. However, it is unclear what…

Logic · Mathematics 2024-07-30 Dragan Mašulović

We show that the Ramsey theory of block sequences in infinite-dimensional discrete vector spaces can be parametrized by perfect sets. As special cases, we prove combinatorial dichotomies for definable families of partitions and linear…

Combinatorics · Mathematics 2026-05-15 Iian B. Smythe

In this paper we investigate algebraic properties of big Ramsey degrees in categories satisfying some mild conditions. As the first nontrivial consequence of the generalization we advocate in this paper we prove that small Ramsey degrees…

Combinatorics · Mathematics 2025-11-27 Dragan Mašulović

Erd\H{o}s and Pach (1983) introduced the natural degree-based generalisations of Ramsey numbers, where instead of seeking large monochromatic cliques in a $2$-edge coloured complete graph, we seek monochromatic subgraphs of high minimum or…

Combinatorics · Mathematics 2018-01-11 Ross Kang , Viresh Patel , Guus Regts

We study an inhomogeneous sparse random graph on [N] = {1, . . . , N } as introduced in a seminal paper by Bollobas, Janson and Riordan (2007): vertices have a type (here in a compact metric space S), and edges between different vertices…

Probability · Mathematics 2023-08-21 Luisa Andreis , Wolfgang König , Heide Langhammer , Robert I. A. Patterson

Given a countable set S of positive reals, we study finite-dimensional Ramsey-theoretic properties of the countable ultrametric Urysohn space with distances in S.

Combinatorics · Mathematics 2019-08-15 L. Nguyen Van Thé

A {\em faithful (unit) distance graph} in $\mathbb{R}^d$ is a graph whose set of vertices is a finite subset of the $d$-dimensional Euclidean space, where two vertices are adjacent if and only if the Euclidean distance between them is…

Combinatorics · Mathematics 2017-12-01 Noga Alon , Andrey Kupavskii

In this paper, we investigate a variant of Ramsey numbers called defective Ramsey numbers where cliques and independent sets are generalized to $k$-dense and $k$-sparse sets, both commonly called $k$-defective sets. We focus on the…

Combinatorics · Mathematics 2021-07-27 Yunus Emre Demirci , Tınaz Ekim , Mehmet Akif Yıldız