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20242026
most citedRicci curvature, diameter and eigenvalues of amply regular graphs

1 citations · 1 across the 10 of their papers we have counts for

collaborators

10 papers

math.DG2026

Topological Rigidity of Contractible 3-Manifolds and Handlebody Interiors under Nonnegative Scalar Curvature

Jiangcheng You, Heng Zhang

We prove that a contractible -manifold admitting a complete Riemannian metric of nonnegative scalar curvature is diffeomorphic to . We also prove that, if the interior $M_…

math.DG2026

Uniform Comparison of Hyperbolic Ball Volumes on the Universal Cover

Heng Zhang

Let denote the simplicial volume of , , and denotes hyperbolic -space. We prove that, i…

math.DG2026

Reciprocal sums of Neumann eigenvalues in non-Euclidean space forms

Jiangcheng You, Heng Zhang

Let be the simply connected space form of dimension and constant sectional curvature . For every bounded connected smooth domain , ass…

math.DG2026

Arbitrarily Many Non-degenerate Local Maxima of First Nonzero Eigenfunctions on Positively Curved Two-spheres

Heng Zhang

We prove that, for every integer , there is a smooth closed Riemannian surface diffeomorphic to , with positive Gaussian curvature, such that …

math.DG2026

Gromov's Euclidean Endpoint Rigidity for the Positive Mass Theorem

Jiangcheng You, Heng Zhang

We prove Gromov's Euclidean endpoint rigidity conjecture. Let be a smooth complete metric on with non-negative scalar curvature. If $$ |g-g_{\Euc}|=o(r^{-1}),\qqua…

math.CO2026

On Lichnerowicz sharp distance-regular graphs

Kaizhe Chen, Shiping Liu, Heng Zhang

The first non-zero Laplacian eigenvalue of a finite graph is bounded below by its minimum Lin--Lu--Yau curvature . This is a discrete analogue of the classical Lichnerowic…

math.AP2025

Existence results for Tzitzéica equation via topological degree method on graphs

Kaizhe Chen, Heng Zhang

We derive some existence results for the solutions of the Tzitzéica equation \begin{equation*} -Δu + h_1(x)e^{Au} + h_2(x)e^{-Bu}=0 \end{equation*} and the generalized Tzitzéica eq…

math.CO2025

Monotonic normalized heat diffusion for distance-regular graphs with classical parameters of diameter

Shiping Liu, Heng Zhang

We prove the monotonic normalized heat diffusion property on distance-regular graphs with classical parameters of diameter . Regev and Shinkar found a Cayley graph for which thi…

math.DG2024★ 1 cited

Ricci curvature, diameter and eigenvalues of amply regular graphs

Kaizhe Chen, Chunyang Hu, Shiping Liu +1

Amply regular graphs are graphs with local distance-regularity constraints. In this paper, we prove a weaker version of a conjecture proposed by Qiao, Park, and Koolen on diameter…

math.CO2024

Curvature and local matchings of conference graphs and extensions

Kaizhe Chen, Shiping Liu, Heng Zhang

We prove a conjecture of Bonini et al. on the precise values of the Lin--Lu--Yau curvature of conference graphs, i.e., strongly regular graphs with parameters . Ou…