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Related papers: Improved Bounds on the Stretch Factor of $Y_4$

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An improved lower bound is given for the decay of conical averages of Fourier transforms of measures, for cones of dimension $d \geq 4$. The proof uses a weighted version of the broad restriction inequality, a narrow decoupling inequality…

Analysis of PDEs · Mathematics 2019-11-05 Terence L. J. Harris

We derive the four-dimensional integrand of the maximal-helicity-violating four-particle form factor for the chiral part of the stress-tensor supermultiplet in planar $\mathcal{N}=4$ super-Yang-Mills theory at two loops. In our integrand…

High Energy Physics - Theory · Physics 2023-06-26 Tushar Gopalka , Enrico Herrmann

We prove an upper bound for the independence number of a graph in terms of the largest Laplacian eigenvalue, and of a certain induced subgraph. Our bound is a refinement of a well-known Hoffman-type bound.

Combinatorics · Mathematics 2023-11-17 Bogdan Nica

For all $s \geq 1$ and $N \geq 1$ there exist sequences $(z_1,\ldots,z_N)$ in $[0,1]^s$ such that the star-discrepancy of these points can be bounded by $$D_N^*(z_1,\ldots,z_N) \leq c \frac{\sqrt{s}}{\sqrt{N}}.$$ The best known value for…

Number Theory · Mathematics 2018-10-29 Hendrik Pasing , Christian Weiß

We prove Cheeger inequalities for p-Laplacians on finite and infinite weighted graphs. Unlike in previous works, we do not impose boundedness of the vertex degree, nor do we restrict ourselves to the normalized Laplacian and, more…

Combinatorics · Mathematics 2018-12-21 Matthias Keller , Delio Mugnolo

We perform an exhaustive search for the minimum 4-regular unit distance graph resulting in a lower bound of 34 vertices.

Combinatorics · Mathematics 2014-01-20 Sascha Kurz

A \emph{square} is a word of the form $uu$, where $u$ is a nonempty finite word. Given a finite word $w$ of length $n$, let $[w]$ denote the corresponding \emph{circular word}, i.e., the set of all cyclic rotations of $w$. We study the…

Combinatorics · Mathematics 2026-05-13 Shuo Li , Yuan Song

We introduce a new parameter, called stretch-width, that we show sits strictly between clique-width and twin-width. Unlike the reduced parameters [BKW '22], planar graphs and polynomial subdivisions do not have bounded stretch-width. This…

Discrete Mathematics · Computer Science 2023-05-23 Édouard Bonnet , Julien Duron

We consider families of finite quantum graphs of increasing size and we are interested in how eigenfunctions are distributed over the graph. As a measure for the distribution of an eigenfunction on a graph we introduce the entropy, it has…

Mathematical Physics · Physics 2014-05-23 Lionel Kameni , Roman Schubert

We consider the problem of determining the inducibility (maximum possible asymptotic density of induced copies) of oriented graphs on four vertices. We provide exact values for more than half of the graphs, and very close lower and upper…

Combinatorics · Mathematics 2022-02-18 Łukasz Bożyk , Andrzej Grzesik , Bartłomiej Kielak

The Pearcey process is a universal point process in random matrix theory and depends on a parameter $\rho \in \mathbb{R}$. Let $N(x)$ be the random variable that counts the number of points in this process that fall in the interval…

Probability · Mathematics 2021-05-06 Christophe Charlier

We derive upper bounds for the eigenvalues of the Kirchhoff Laplacian on a compact metric graph depending on the graph's genus g. These bounds can be further improved if $g = 0$, i.e. if the metric graph is planar. Our results are based on…

Spectral Theory · Mathematics 2020-04-10 Marvin Plümer

The Cheeger constant of a graph, or equivalently its coboundary expansion, quantifies the expansion of the graph. This notion assumes an implicit choice of a coefficient group, namely, $\mathbb{F}_2$. In this paper, we study Cheeger-type…

Combinatorics · Mathematics 2025-04-29 Uriya A. First , Tali Kaufman

We prove distance bounds for graphs possessing positive Bakry-\'Emery curvature apart from an exceptional set, where the curvature is allowed to be non-positive. If the set of non-positively curved vertices is finite, then the graph admits…

Differential Geometry · Mathematics 2019-03-26 Shiping Liu , Florentin Münch , Norbert Peyerimhoff , Christian Rose

For a positive integer $k$ and an ordered set of $n$ points in the plane, define its k-sector ordered Yao graphs as follows. Divide the plane around each point into $k$ equal sectors and draw an edge from each point to its closest…

Combinatorics · Mathematics 2025-04-29 Péter Ágoston , Adrian Dumitrescu , Arsenii Sagdeev , Karamjeet Singh , Ji Zeng

We determine new upper bounds for the clique numbers of strongly regular graphs in terms of their parameters. These bounds improve on the Delsarte bound for infinitely many feasible parameter tuples for strongly regular graphs, including…

Combinatorics · Mathematics 2019-01-31 Gary R. W. Greaves , Leonard H. Soicher

A Poisson point process of unit intensity is placed in the square $[0,n]^2$. An increasing path is a curve connecting $(0,0)$ with $(n,n)$ which is non-decreasing in each coordinate. Its length is the number of points of the Poisson process…

Probability · Mathematics 2018-08-28 Partha Dey , Mathew Joseph , Ron Peled

The study of upper density problems on Ramsey theory was initiated by Erd\H{o}s and Galvin in 1993. In this paper we are concerned with the following problem: given a fixed finite graph $F$, what is the largest value of $\lambda$ such that…

Combinatorics · Mathematics 2020-10-27 József Balogh , Ander Lamaison

The critical exponent $E(\mathbf u)$ of an infinite sequence $\mathbf u$ over a finite alphabet expresses the maximal repetition of a factor in $\mathbf u$. By the famous Dejean's theorem, $E(\mathbf u) \geq 1+\frac1{d-1}$ for every $d$-ary…

Combinatorics · Mathematics 2022-08-02 Lubomíra Dvořáková , Daniela Opočenská , Edita Pelantová

We present new values and bounds on the (normalised) closeness centrality $\bar{\mathsf{C}}_C$ of connected graphs and on its product $\bar{l}\bar{\mathsf{C}}_C$ with the mean distance $\bar{l}$ of these graphs. Our main result presents the…

Combinatorics · Mathematics 2023-07-19 Thomas Britz , Xin Hu , Abdellah Islam , Hopein Christofen Tang