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Related papers: Ricci curvature, Bruhat graphs and Coxeter groups

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Characterizing shapes of high-dimensional objects via Ricci curvatures plays a critical role in many research areas in mathematics and physics. However, even though several discretizations of Ricci curvatures for discrete combinatorial…

Data Structures and Algorithms · Computer Science 2023-08-14 Bhaskar DasGupta , Elena Grigorescu , Tamalika Mukherjee

In this note we discuss the fundamental groups and diameters of positively Ricci curved $n$-manifolds. We use a method combining the results about equivarient Hausdorff convergence developed by Fukaya and Yamaguchi with the Ricci version of…

Differential Geometry · Mathematics 2007-05-23 Wen-Haw Chen , Jyh-Yang Wu

In this paper, we establish Buser type inequalities, i.e., upper bounds for eigenvalues in terms of Cheeger constants. We prove the Buser's inequality for an infinite but locally finite connected graph with Ricci curvature lower bounds.…

Differential Geometry · Mathematics 2018-10-30 Shuang Liu

We study a new notion of Ricci curvature that applies to Markov chains on discrete spaces. This notion relies on geodesic convexity of the entropy and is analogous to the one introduced by Lott, Sturm, and Villani for geodesic measure…

Metric Geometry · Mathematics 2015-06-03 Matthias Erbar , Jan Maas

We show that Lusztig's $a$-function of a Coxeter group is bounded if the Coxeter group has a complete graph (i.e. any two vertices are joined) and the cardinalities of finite parabolic subgroups of the Coxeter group have a common upper…

Quantum Algebra · Mathematics 2011-06-14 Nanhua Xi

In this paper, we consider the Ricci curvature of a directed graph, based on Lin-Lu-Yau's definition. We give some properties of the Ricci curvature, including conditions for a directed regular graph to be Ricci-flat. Moreover, we calculate…

Combinatorics · Mathematics 2018-08-24 Taiki Yamada

We present a notion of super Ricci flow for time-dependent finite weighted graphs. A challenging feature is that these flows typically encounter singularities where the underlying graph structure changes. Our notion is robust enough to…

Differential Geometry · Mathematics 2018-05-18 Matthias Erbar , Eva Kopfer

Discrete curvatures are quantities associated to the nodes and edges of a graph that reflect the local geometry around them. These curvatures have a rich mathematical theory and they have recently found success as a tool to analyze networks…

Physics and Society · Physics 2024-08-02 Michelle Roost , Karel Devriendt , Giulio Zucal , Jürgen Jost

In this note, we provide Steinerberger curvature formulas for block graphs, discuss curvature relations between two graphs and the graph obtained by connecting them via a bridge, and show that self-centered Bonnet-Myers sharp graphs are…

Combinatorics · Mathematics 2025-10-14 David Cushing , Supanat Kamtue , Erin Law , Shiping Liu , Florentin Münch , Norbert Peyerimhoff

Connections between continuous and discrete worlds tend to be elusive. One example is curvature. Even though there exist numerous nonequivalent definitions of graph curvature, none is known to converge in any limit to any traditional…

Mirror graphs were introduced by Bre\v{s}ar et al. in 2004 as an intriguing class of graphs: vertex-transitive, isometrically embeddable into hypercubes, having a strong connection with regular maps and polytope structure. In this article…

Combinatorics · Mathematics 2016-09-05 Tilen Marc

We use the framework used by Bakry and Emery in their work on logarithmic Sobolev inequalities to define a notion of coarse Ricci curvature on smooth metric measure spaces alternative to the notion proposed by Y. Ollivier. This function can…

Differential Geometry · Mathematics 2015-05-18 Antonio Ache , Micah Warren

We investigate the rigidity problem for the sharp spectral gap on Finsler manifolds of weighted Ricci curvature bound $\text{Ric}_{\infty} \geq K > 0$. Our main results show that if the equality holds, the manifold necessarily admits a…

Differential Geometry · Mathematics 2022-07-26 Cong Hung Mai

We develop a new and systematic method for proving entropic Ricci curvature lower bounds for Markov chains on discrete sets. Using different methods, such bounds have recently been obtained in several examples (e.g., 1-dimensional birth and…

Probability · Mathematics 2016-06-28 Max Fathi , Jan Maas

We consider random right-angled Coxeter groups, $W_{\Gamma}$, whose presentation graph $\Gamma$ is taken to be an Erd\H{o}s--R\'enyi random graph, i.e., $\Gamma\sim \mathcal{G}_{n,p}$. We use techniques from probabilistic combinatorics to…

Probability · Mathematics 2025-02-26 Jason Behrstock , R. Altar Ciceksiz , Victor Falgas-Ravry

We show that any closed biquotient with finite fundamental group admits metrics of positive Ricci curvature. Also, let M be a closed manifold on which a compact Lie group G acts with cohomogeneity one, and let L be a closed subgroup of G…

Differential Geometry · Mathematics 2007-05-23 Lorenz Schwachhoefer , Wilderich Tuschmann

We establish a Harnack inequality for finite connected graphs with non-negative Ricci curvature. As a consequence, we derive an eigenvalue lower bound, extending previous results for Ricci flat graphs.

Combinatorics · Mathematics 2012-07-30 Fan Chung , Yong Lin , Shing-Tung Yau

We explore properties of generalized Paley graphs and we extend a result of Lim and Praeger by providing a more precise description of the connected components of disconnected generalized Paley graphs. This result leads to a new…

Combinatorics · Mathematics 2024-09-13 Vincent Bonini , Daniel Chamberlin , Stephen Cook , Parthiv Seetharaman , Tri Tran

We prove sharp spectral gap estimates on compact manifolds with integral curvature bounds. We generalize the results of Kr\"oger (Kr\"oger '92) as well as of Bakry and Qian (Bakry-Qian '00) to the case of integral curvature and confirm the…

Differential Geometry · Mathematics 2026-05-28 Xavier Ramos Olivé , Shoo Seto , Malik Tuerkoen

An equivalent definition of entropic Ricci curvature on discrete spaces was given in terms of the global gradient estimate. With a particular choice of the density function $\rho$, we obtain a localized gradient estimate, which in turns…

Probability · Mathematics 2020-03-04 Supanat Kamtue