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Related papers: Projective Fra\"{\i}ss\'{e} limits of trees

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In this paper we study the Spanning Tree Congestion problem, where we are given a graph $G=(V,E)$ and are asked to find a spanning tree $T$ of minimum maximum congestion. Here, the congestion of an edge $e\in T$ is the number of edges…

Data Structures and Algorithms · Computer Science 2026-05-28 Michael Lampis , Valia Mitsou , Edouard Nemery , Yota Otachi , Manolis Vasilakis , Daniel Vaz

An $r$-uniform hypergraph is a tight $r$-tree if its edges can be ordered so that every edge $e$ contains a vertex $v$ that does not belong to any preceding edge and the set $e-v$ lies in some preceding edge. A conjecture of Kalai [Kalai],…

Combinatorics · Mathematics 2017-12-13 Zoltán Füredi , Tao Jiang , Alexandr Kostochka , Dhruv Mubayi , Jacques Verstraëte

Trees without vertices of degree $2$ are sometimes named topological trees. In this work, we bring forward the study of the inducibility of (rooted) topological trees with a given number of leaves. The inducibility of a topological tree $S$…

Combinatorics · Mathematics 2018-02-20 Audace Amen Vioutou Dossou-Olory , Stephan Wagner

We study the first-order almost-sure theories for classes of finite structures that are specified by homomorphically forbidding a set $\mathcal{F}$ of finite structures. If $\mathcal{F}$ consists of undirected graphs, a full description of…

Combinatorics · Mathematics 2024-06-24 Manuel Bodirsky , Colin Jahel

Topological behavior, such as chaos, irreducibility, and mixing of a one-sided shift of finite type, is well elucidated. Meanwhile, the investigation of multidimensional shifts, for instance, textile systems is difficult and only a few…

Dynamical Systems · Mathematics 2015-09-10 Jung-Chao Ban , Chih-Hung Chang

Two rooted locally finite trees are considered equivalent if both can be embedded into each other as topological minors by means of tree-order preserving mappings. By exploiting Nash-William's Theorem, Matthiesen provided a non-constructive…

Combinatorics · Mathematics 2016-04-18 J. Bruno

This paper introduces decorated merge trees (DMTs) as a novel invariant for persistent spaces. DMTs combine both $\pi_0$ and $H_n$ information into a single data structure that distinguishes filtrations that merge trees and persistent…

Algebraic Topology · Mathematics 2021-07-29 Justin Curry , Haibin Hang , Washington Mio , Tom Needham , Osman Berat Okutan

The search for universality in random triangulations of manifolds, like those featuring in (Euclidean) Dynamical Triangulations, is central to the random geometry approach to quantum gravity. In case of the 3-sphere, or any other manifold…

Combinatorics · Mathematics 2022-03-31 Timothy Budd , Luca Lionni

Motivated by a conjecture of Gy\'arf\'as, recently B\"ottcher, Hladk\'y, Piguet, and Taraz showed that every collection $T_1,\dots,T_t$ of trees on $n$ vertices with $\sum_{i=1}^te(T_i)\leq \binom{n}{2}$ and with bounded maximum degree, can…

Combinatorics · Mathematics 2016-04-20 Silvia Messuti , Vojtěch Rödl , Mathias Schacht

We continue to develop an obstruction theory for embedding 2-spheres into 4-manifolds in terms of Whitney towers. The proposed intersection invariants take values in certain graded abelian groups generated by labelled trivalent trees, and…

Geometric Topology · Mathematics 2007-05-23 Rob Schneiderman , Peter Teichner

We develop the theory of homogeneous Polish ultrametric structures. Our starting point is a Fraisse class of finite structures and the crucial tool is the universal homogeneous epimorphism. The new Fraisse limit is an inverse limit,…

Logic · Mathematics 2023-11-10 W. Kubiś , Ch. Pech , M. Pech

We prove that the group of automorphisms of the generic meet-tree expansion of an infinite non-unary free Fra\"{\i}ss\'{e} limit over a finite relational language is simple. As a prototypical case, the group of automorphism of the Rado…

Logic · Mathematics 2025-10-01 Itay Kaplan , Binyamin Riahi , Arturo Rodriguez Fanlo

We study a model of random $\mathcal{R}$-enriched trees that is based on weights on the $\mathcal{R}$-structures and allows for a unified treatment of a large family of random discrete structures. We establish distributional limits…

Probability · Mathematics 2018-12-12 Benedikt Stufler

A theorem of Frieze from 1985 asserts that the total weight of the minimum spanning tree of the complete graph $K_n$ whose edges get independent weights from the distribution $UNIFORM[0,1]$ converges to Ap\'ery's constant in probability, as…

Combinatorics · Mathematics 2025-04-14 Jan Hladký , Gopal Viswanathan

In this expository paper, we present a construction of tree modules and combine it with (infinite dimensional) tilting theory and relative Mittag-Leffler conditions in order to explore limits of the approximation theory of modules. We also…

Representation Theory · Mathematics 2019-01-08 Jan Trlifaj

A variant of the Erd\H{o}s-S\'os conjecture, posed by Havet, Reed, Stein and Wood, states that every graph with minimum degree at least $\lfloor 2k/3 \rfloor$ and maximum degree at least $k$ contains a copy of every tree with $k$ edges.…

Combinatorics · Mathematics 2025-12-19 Alexey Pokrovskiy , Leo Versteegen , Ella Williams

In this paper we obtain precise asymptotics for certain families of graphs, namely circulant graphs and degenerating discrete tori. The asymptotics contain interesting constants from number theory among which some can be interpreted as…

Combinatorics · Mathematics 2016-07-28 Justine Louis

We show, under natural conditions, that uniform rooted trees with fixed degree sequence converge after renormalization toward inhomogeneous continuum random trees (ICRT). We also provide a sharp upper-bound for the tail of their heights. We…

Probability · Mathematics 2025-12-23 Arthur Blanc-Renaudie

Tree sets are abstract structures that can be used to model various tree-shaped objects in combinatorics. Finite tree sets can be represented by finite graph-theoretical trees. We extend this representation theory to infinite tree sets.…

Combinatorics · Mathematics 2025-05-16 J. Pascal Gollin , Jay Lilian Kneip

Consider the d-dimensional lattice Z^d where each vertex is ``open'' or ``closed'' with probability p or 1-p, respectively. An open vertex v is connected by an edge to the closest open vertex w such that the dth co-ordinates of v and w…

Probability · Mathematics 2016-09-07 Sreela Gangopadhyay , Rahul Roy , Anish Sarkar