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Related papers: The Ricci curvature on directed graphs

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We have performed an empirical comparison of two distinct notions of discrete Ricci curvature for graphs or networks, namely, the Forman-Ricci curvature and Ollivier-Ricci curvature. Importantly, these two discretizations of the Ricci…

Differential Geometry · Mathematics 2018-06-12 Areejit Samal , R. P. Sreejith , Jiao Gu , Shiping Liu , Emil Saucan , Jürgen Jost

Curvature is a fundamental geometric characteristic of smooth spaces. In recent years different notions of curvature have been developed for combinatorial discrete objects such as graphs. However, the connections between such discrete…

Probability · Mathematics 2023-11-09 Pim van der Hoorn , Gabor Lippner , Carlo Trugenberger , Dmitri Krioukov

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…

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

The definition of Ricci curvature on graphs in Bakry-\'Emery's sense based on curvature dimension condition was introduced by Lin and Yau [\emph{Math. Res. Lett.}, 2010]. Hua and Lin [\emph{Comm. Anal. Geom.}, 2019] classified unweighted…

Combinatorics · Mathematics 2024-08-20 Huiqiu Lin , Zhe You

We investigate the Ollivier-Ricci curvature and its modification introduced by Lin, Lu, and Yau on locally finite graphs. The main contribution of this work is a lower bound on the minimum vertex degree of a graph ensuring non-negative…

Combinatorics · Mathematics 2025-02-07 Moritz Hehl

The notion of the Ricci curvature is defined for sprays on a manifold. With a volume form on a manifold, every spray can be deformed to a projective spray. The Ricci curvature of a projective spray is called the projective Ricci curvature.…

Differential Geometry · Mathematics 2020-08-05 Zhongmin Shen , Liling Sun

We consider the normalized Laplace operator for directed graphs with positive and negative edge weights. This generalization of the normalized Laplace operator for undirected graphs is used to characterize directed acyclic graphs. Moreover,…

Combinatorics · Mathematics 2012-02-01 Frank Bauer

In this paper, we classify graphs with nonnegative Lin-Lu-Yau-Ollivier Ricci curvature, maximum degree at most 3 and diameter at least 6.

Differential Geometry · Mathematics 2021-10-14 Fengwen Han , Tao Wang

We introduce a notion of Ricci curvature for Cayley graphs that can be thought of as "medium-scale" because it is neither infinitesimal nor asymptotic, but based on a chosen finite radius parameter. We argue that it gives the foundation for…

Group Theory · Mathematics 2020-07-06 Assaf Bar-Natan , Moon Duchin , Robert Kropholler

We study the Ollivier-Ricci curvature of graphs as a function of the chosen idleness. We show that this idleness function is concave and piecewise linear with at most $3$ linear parts, with at most $2$ linear parts in the case of a regular…

Combinatorics · Mathematics 2017-07-05 David Bourne , David Cushing , Shiping Liu , Florentin Münch , Norbert Peyerimhoff

In the present work, we study the properties of biological networks by applying analogous notions of fundamental concepts in Riemannian geometry and optimal mass transport to discrete networks described by weighted graphs. Specifically, we…

Molecular Networks · Quantitative Biology 2017-12-11 Maryam Pouryahya , James Mathews , Allen Tannenbaum

We prove Li-Yau type gradient bounds for the heat equation either on manifolds with fixed metric or under the Ricci flow. In the former case the curvature condition is $|Ric^-| \in L^p$ for some $p>n/2$, or $\sup_\M \int_\M…

Differential Geometry · Mathematics 2018-05-30 Qi S Zhang , Meng Zhu

Lin, Lu, and Yau formulated the Ricci curvature of edges in simple undirected graphs[2]. Using their formulations, we calculate the Ricci curvatures of Cayley graphs for the dihedral groups, the general quaternion groups, and cyclic groups…

Combinatorics · Mathematics 2024-01-17 Iwao Mizukai , Akifumi Sako

Discrete forms of the scalar, sectional and Ricci curvatures are constructed on simplicial piecewise flat triangulations of smooth manifolds, depending directly on the simplicial structure and a choice of dual tessellation. This is done by…

Differential Geometry · Mathematics 2018-06-05 Rory Conboye , Warner A. Miller

This is a preliminary study of the equation of motion of Euclidean classical gravity on a graph, based on the Lin-Lu-Yau Ricci curvature on graphs. We observe that the constant edge weights configuration gives the unique solution on an…

Mathematical Physics · Physics 2020-06-15 An Huang , Bogdan Stoica , Xuyang Xia , Xiao Zhong

We introduce a novel definition of curvature for hypergraphs, a natural generalization of graphs, by introducing a multi-marginal optimal transport problem for a naturally defined random walk on the hypergraph. This curvature, termed…

Information Theory · Computer Science 2018-03-26 Shahab Asoodeh , Tingran Gao , James Evans

Giving explicit parametrizations of discrete constant Gaussian curvature surfaces of revolution that are defined from an integrable systems approach, we study Ricci flow for discrete surfaces, and see how discrete surfaces of revolution…

Differential Geometry · Mathematics 2023-12-14 Naoya Suda

In this paper we give an explicit bound of $\Delta_{g(t)}u(t)$ and the local curvature estimates for the Ricci-harmonic flow under the condition that the Ricci curvature is bounded along the flow. In the second part these local curvature…

Differential Geometry · Mathematics 2018-10-24 Yi Li

We investigate the prescribed Ricci curvature problem in the class of left-invariant naturally reductive Riemannian metrics on a non-compact simple Lie group. We obtain a number of conditions for the solvability of the underlying equations…

Differential Geometry · Mathematics 2024-12-24 Romina M. Arroyo , Mark D. Gould , Artem Pulemotov