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Related papers: Structural Ramsey Theory and the Extension Propert…

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Under no additional assumptions, in this paper we construct a Ramsey expansion for every category of finite objects with finite small Ramsey degrees. Our construction is based on the relationship between small Ramsey degrees, weak…

Logic · Mathematics 2022-08-25 Dragan Mašulović , Andy Zucker

For each $n\geq 2$, we show that the class of all finite $n$-dimensional partial orders, when expanded with $n$ linear orders which realize the partial order, forms a Fra\"iss\'e class and identify its Fra\"iss\'e limit…

Combinatorics · Mathematics 2025-01-16 Iian B. Smythe , Mithuna Threz , Max Wiebe

We present a short and self-contained proof of the extension property for partial isometries of the class of all finite metric spaces.

Combinatorics · Mathematics 2025-10-01 Jan Hubička , Matěj Konečný , Jaroslav Nešetřil

One way of studying a relational structure is to investigate functions which are related to that structure and which leave certain aspects of the structure invariant. Examples are the automorphism group, the self-embedding monoid, the…

Logic · Mathematics 2011-05-31 Manuel Bodirsky , Michael Pinsker

In contrast to the abundance of "direct" Ramsey results for classes of finite structures (such as finite ordered graphs, finite ordered metric spaces and finite posets with a linear extension), in only a handful of cases we have a…

Combinatorics · Mathematics 2018-07-06 Dragan Mašulović , Bojana Pantić

We study Ramsey expansions of certain homogeneous 3-hypertournaments. We show that they exhibit an interesting behaviour and, in one case, they seem not to submit to current gold-standard methods for obtaining Ramsey expansions. This makes…

Combinatorics · Mathematics 2022-01-11 Gregory Cherlin , Jan Hubička , Matěj Konečný , Jaroslav Nešetřil

This article highlights historical achievements in the partition theory of countable homogeneous relational structures, and presents recent work, current trends, and open problems. Exciting recent developments include new methods involving…

Logic · Mathematics 2021-10-05 Natasha Dobrinen

Among Thurston maps (orientation-preserving, postcritically finite branched coverings of the 2-sphere to itself), those that arise as subdivision maps of a finite subdivision rule form a special family. For such maps, we investigate…

Dynamical Systems · Mathematics 2015-08-04 William J. Floyd , Walter R. Parry , Kevin M. Pilgrim

Close connections between various notions of entropy and the apparatus of category theory have been observed already in the 1980s and more vigorously developed in the past ten years. The starting point of the paper is the recent categorical…

Combinatorics · Mathematics 2022-04-25 Dragan Mašulović

Given a structure $M$ we introduce infinitary logic expansions, which generalise the Morleyisation. We show that these expansions are tame, in the sense that they preserve and reflect both the Embedding Ramsey Property (ERP) and the…

Logic · Mathematics 2023-06-29 Nadav Meir , Aris Papadopoulos

Given two Fra\"iss\'e-like classes with generic limits, we ask whether we can merge the two classes into one class with a generic limit. We study the properties of these merges and their generics, as well as their connections to structural…

Logic · Mathematics 2024-11-19 Morgan Bryant

We develop a transfer principle of structural Ramsey theory from finite structures to ultraproducts. We show that under certain mild conditions, when a class of finite structures has finite small Ramsey degrees, under the (Generalized)…

Logic · Mathematics 2025-12-03 Dana Bartošová , Mirna Džamonja , Rehana Patel , Lynn Scow

We prove some results on the border of Ramsey theory (finite partition calculus) and model theory. Also a beginning of classification theory of finite models in undertaken.

Logic · Mathematics 2016-09-06 Doug Ensley , Rami Grossberg

Topological Ramsey spaces are spaces which support infinite dimensional Ramsey theory similarly to the Ellentuck space. Each topological Ramsey space is endowed with a partial ordering which can be modified to a $\sigma$-closed `almost…

Logic · Mathematics 2018-05-23 Natasha Dobrinen

We study the Ramsey property for vector spaces over finite fields with bilinear forms. We prove that symplectic spaces over finite fields do not have the Ramsey property. We also describe vector spaces with skew symmetric bilinear forms and…

Logic · Mathematics 2025-03-12 Aleksander Ivanov , Frédéric Jaffrennou

We apply the Dual Ramsey Theorem of Graham and Rothschild to prove the Ramsey property for classes of finite Boolean algebras with distinguished ideals. This allows us to compute the universal minimal flow of the group of automorphisms of…

Dynamical Systems · Mathematics 2013-01-17 Dana Bartošová

The celebrated theorem of Kechris, Pestov and Todor\v{c}evi\'c connecting structural Ramsey theory with topological dynamics has as a consequence that the Fra\"{\i}ss\'e limit of a Ramsey class of non-trivial finite relational structures…

Logic · Mathematics 2025-12-08 Peter J. Cameron , Siavash Lashkarighouchani

We examine properties of generic automorphisms of the random poset, with the goal of explicitly characterizing them. We associate to each automorphism an auxiliary first-order structure, consisting of the random poset equipped with an…

Logic · Mathematics 2021-01-01 Dakota Thor Ihli

We will review the main results concerning the automorphism groups of saturated structures which were obtained during the two last decades. The main themes are: the small index property in the countable and uncountable cases; the…

Logic · Mathematics 2007-05-23 Daniel Lascar

We offer a criterion for showing that the automorphism group of an ultrahomogeneous structure is topologically 2-generated and even has a cyclically dense conjugacy class. We then show how finite topological rank of the automorphism group…

Group Theory · Mathematics 2019-08-26 Itay Kaplan , Pierre Simon