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Related papers: Heat kernels are not uniform expanders

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We consider a quantum graph where the operator contains a potential. We show that this operator admits a heat kernel. Under some assumptions on the potential, this heat kernel admits an asymptotic expansion at t=0 with coefficients that…

Analysis of PDEs · Mathematics 2012-12-13 Ralf Rueckriemen

Consider an infinite planar graph with uniform polynomial growth of degree d > 2. Many examples of such graphs exhibit similar geometric and spectral properties, and it has been conjectured that this is necessary. We present a family of…

Probability · Mathematics 2021-03-11 Farzam Ebrahimnejad , James R. Lee

We study the existence and uniqueness of the heat kernel on infinite, locally finite, connected graphs. For general graphs, a uniqueness criterion, shown to be optimal, is given in terms of the maximal valence on spheres about a fixed…

Spectral Theory · Mathematics 2008-04-24 Radoslaw K. Wojciechowski

For every infinite sequence of simple groups of Lie type of growing rank we exhibit connected Cayley graphs of degree at most 10 such that the isoperimetric number of these graphs converges to 0. This proves that these graphs do not form a…

Combinatorics · Mathematics 2013-02-12 Gabor Somlai

We establish general estimates for simple random walk on an arbitrary infinite random graph, assuming suitable bounds on volume and effective resistance for the graph. These are generalizations of the results in \cite[Section 1,2]{BJKS},…

Probability · Mathematics 2008-08-01 Takashi Kumagai , Jun Misumi

We consider continuous time simple random walks with arbitrary speed measure $\theta$ on infinite weighted graphs. Write $p_t(x,y)$ for the heat kernel of this process. Given on-diagonal upper bounds for the heat kernel at two points…

Probability · Mathematics 2012-02-01 Matthew Folz

In this note we give a short proof that graphs having no linearly small F{\o}lner sets can be partitioned into a union of expanders. We use this fact to prove a partition result for graphs admitting linearly small maximal F{\o}lner sets and…

Combinatorics · Mathematics 2021-01-13 Federico Vigolo

It is shown that there exists a sequence of 3-regular graphs $\{G_n\}_{n=1}^\infty$ and a Hadamard space $X$ such that $\{G_n\}_{n=1}^\infty$ forms an expander sequence with respect to $X$, yet random regular graphs are not expanders with…

Metric Geometry · Mathematics 2015-11-03 Manor Mendel , Assaf Naor

Hypergraphs are an invaluable tool to understand many hidden patterns in large data sets. Among many ways to represent hypergraph, one useful representation is that of weighted clique expansion. In this paper, we consider this…

Combinatorics · Mathematics 2018-08-15 Ashwin Guha , Ambedkar Dukkipati

We consider a class of growing random graphs obtained by creating vertices sequentially one by one: at each step, we choose uniformly the neighbours of the newly created vertex; its degree is a random variable with a fixed but arbitrary…

Combinatorics · Mathematics 2013-11-13 Svante Janson , Simone Severini

This paper studies anchored expansion, a non-uniform version of the strong isoperimetric inequality. We show that every graph with i-anchored expansion contains a subgraph with isoperimetric (Cheeger) constant at least i. We prove a…

Probability · Mathematics 2011-11-10 Balint Virag

Nowhere dense classes of graphs are very general classes of uniformly sparse graphs with several seemingly unrelated characterisations. From an algorithmic perspective, a characterisation of these classes in terms of uniform quasi-wideness,…

Discrete Mathematics · Computer Science 2018-09-06 Stephan Kreutzer , Roman Rabinovich , Sebastian Siebertz

There exists a graph with two vertices x and y such that the ratio of the heat kernels p(x,x;t)/p(y,y;t) does not converge as t goes to infinity.

Probability · Mathematics 2011-11-22 Gady Kozma

Many problems and conjectures in extremal combinatorics concern polynomial inequalities between homomorphism densities of graphs where we allow edges to have real weights. Using the theory of graph limits, we can equivalently evaluate…

Combinatorics · Mathematics 2022-07-26 Grigoriy Blekherman , Annie Raymond , Fan Wei

A paradigm that was successfully applied in the study of both pure and algorithmic problems in graph theory can be colloquially summarized as stating that "any graph is close to being the disjoint union of expanders". Our goal in this paper…

Combinatorics · Mathematics 2015-02-03 Guy Moshkovitz , Asaf Shapira

Meta-theorems for polynomial (linear) kernels have been the subject of intensive research in parameterized complexity. Heretofore, meta-theorems for linear kernels exist on graphs of bounded genus, $H$-minor-free graphs, and…

Benjamini and Schramm introduced the notion of distributional limit of a sequence of graphs with uniformly bounded valence and studied such limits in the case that the involved graphs are planar. We investigate distributional limits of…

Metric Geometry · Mathematics 2013-09-05 Hossein Namazi , Pekka Pankka , Juan Souto

We consider the asymptotics of the discrete heat kernel on isoradial graphs for the case where the time and the edge lengths tend to zero simultaneously. Depending on the asymptotic ratio between time and edge lengths, we show that two…

Probability · Mathematics 2024-01-24 Simon Schwarz , Anja Sturm , Max Wardetzky

In this paper, we prove the equivalent of ultracontractive bound of heat semigroup or the uniform upper bound of the heat kernel with the Nash inequality, Log-Sobolev inequalities on graphs. We also show that under the assumption of volume…

Differential Geometry · Mathematics 2015-02-09 Yong Lin , Shuang Liu , Hongye Song

Hypergraph expanders are hypergraphs with surprising, non-intuitive expansion properties. In a recent paper, the first author gave a simple construction, which can be randomized, of $3$-uniform hypergraph expanders with polylogarithmic…

Combinatorics · Mathematics 2020-07-27 David Conlon , Jonathan Tidor , Yufei Zhao
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