English
Related papers

Related papers: Random Complexes and l^2-Betti Numbers

200 papers

We define a variant of Benjamini-Schramm convergence for finite simplicial complexes with the action of a fixed finite group G which leads to the notion of random rooted simplicial G-complexes. For every random rooted simplicial G-complex…

Algebraic Topology · Mathematics 2019-05-15 Steffen Kionke , Michael Schrödl-Baumann

We provide a finite equational presentation of graphs of treewidth at most three, solving an instanceof an open problem by Courcelle and Engelfriet. We use a syntax generalising series-parallel expressions, denoting graphs with a small…

Logic in Computer Science · Computer Science 2025-01-23 Amina Doumane , Samuel Humeau , Damien Pous

Motivated by limits of critical inhomogeneous random graphs, we construct a family of sequences of measured metric spaces that we call continuous multiplicative graphs, that are expected to be the universal limit of graphs related to the…

Probability · Mathematics 2020-02-07 Nicolas Broutin , Thomas Duquesne , Minmin Wang

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

We prove that if a unimodular random rooted graph is recurrent, the number of ends of its uniform spanning tree is almost surely equal to the number of ends of the graph. Together with previous results in the transient case, this completely…

Probability · Mathematics 2023-01-11 Diederik van Engelenburg , Tom Hutchcroft

We consider a uniform spanning tree in a $\delta$-square grid approximation of a planar domain $\Omega$. For given integer $n\ge 2$, we condition the tree on the following $n$-arm event: we pick $n$ branches, emanating from $n$ points…

Probability · Mathematics 2025-12-24 Nathanaël Berestycki , Marcin Lis , Mingchang Liu , Eveliina Peltola

We study some sequences of polynomials that appear when we consider the successive derivatives of the tree function (or Lambert's W function). We show in particular that they are related with a generalization of Cayley trees, called Greg…

Combinatorics · Mathematics 2017-09-13 Matthieu Josuat-Vergès

We prove that the L^2-Betti numbers of a unimodular locally compact group G coincide, up to a natural scaling constant, with the L^2-Betti numbers of the countable equivalence relation induced on a cross section of any essentially free…

Group Theory · Mathematics 2015-04-21 David Kyed , Henrik Densing Petersen , Stefaan Vaes

We consider two notions describing how one finite graph may be larger than another. Using them, we prove several theorems for such pairs that compare the number of spanning trees, the return probabilities of random walks, and the number of…

Combinatorics · Mathematics 2018-09-10 Russell Lyons

We investigate the bottom of the spectra of infinite quantum graphs, i.e., Laplace operators on metric graphs having infinitely many edges and vertices. We introduce a new definition of the isoperimetric constant for quantum graphs and then…

Spectral Theory · Mathematics 2018-12-17 Aleksey Kostenko , Noema Nicolussi

The notion of tree entropy was introduced by the author as a normalized limit of the number of spanning trees in finite graphs, but is defined on random infinite rooted graphs. We give some new expressions for tree entropy; one uses…

Combinatorics · Mathematics 2010-04-27 Russell Lyons

A graph can be regarded as an electrical network in which each edge is a resistor. This point of view relates combinatorial quantities, such as the number of spanning trees, to electrical ones such as effective resistance. The second and…

Combinatorics · Mathematics 2023-08-30 Art M. Duval , Woong Kook , Kang-Ju Lee , Jeremy L. Martin

A shelling of a graph, viewed as an abstract simplicial complex that is pure of dimension 1, is an ordering of its edges such that every edge is adjacent to some other edges appeared previously. In this paper, we focus on complete bipartite…

Combinatorics · Mathematics 2021-02-11 Yibo Gao , Junyao Peng

The vertices of the Cayley graph of a finitely generated semigroup form a set of sites which can be labeled by elements of a finite alphabet in a manner governed by a nonnegative real interaction matrix, respecting nearest neighbor…

Dynamical Systems · Mathematics 2022-10-07 Karl Petersen , Ibrahim Salama

A classical result by Otter shows that the complete graph has an exponential number of non-isomorphic spanning trees. This was recently extended by Lee to every almost regular graph of sufficiently large degree. In this paper, we consider…

Combinatorics · Mathematics 2026-03-19 Veronica Bitonti , Lukas Michel , Alex Scott

We prove that in both the free and the wired uniform spanning forest (FUSF and WUSF) of any unimodular random rooted network (in particular, of any Cayley graph), it is impossible to distinguish the connected components of the forest from…

Probability · Mathematics 2018-05-01 Tom Hutchcroft , Asaf Nachmias

In this paper we consider the asymptotic behavior of invariants such as Betti numbers, minimal numbers of generators of singular homology, the order of the torsion subgroup of singular homology, and torsion invariants. We will show that all…

Algebraic Topology · Mathematics 2012-10-18 Wolfgang Lueck

The aim of this chapter is to provide an adequate graph theoretic framework for the description of periodic bifurcations which have recently been discovered in descendant trees of finite p-groups. The graph theoretic concepts of rooted…

Group Theory · Mathematics 2017-01-30 Daniel C. Mayer

We introduce the extension graph of graph product of groups and study its geometry. This enables us to study properties of graph product by exploiting large scale geometry of its defining graph. In particular, we show that the extension…

Group Theory · Mathematics 2026-03-17 Koichi Oyakawa

We introduce a concept of tree-graded metric space and we use it to show quasi-isometry invariance of certain classes of relatively hyperbolic groups, to obtain a characterization of relatively hyperbolic groups in terms of their asymptotic…

Geometric Topology · Mathematics 2009-09-29 Cornelia Drutu , Mark Sapir