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Related papers: Bounds on eigenvalue ratios of quantum graphs

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We use two variational techniques to prove upper bounds for sums of the lowest several eigenvalues of matrices associated with finite, simple, combinatorial graphs. These include estimates for the adjacency matrix of a graph and for both…

Spectral Theory · Mathematics 2013-08-27 Evans M. Harell , Joachim Stubbe

We deal with eigenvalue problems for the Laplacian with varying mixed boundary conditions, consisting in homogeneous Neumann conditions on a vanishing portion of the boundary and Dirichlet conditions on the complement. By the study of an…

Analysis of PDEs · Mathematics 2022-03-11 Veronica Felli , Benedetta Noris , Roberto Ognibene

Quantum graphs are defined by having a Laplacian defined on the edges of a metric graph with boundary conditions on each vertex such that the resulting operator, $\mathbf{L}$, is self-adjoint. We use Neumann boundary conditions although we…

Spectral Theory · Mathematics 2025-12-02 Mats-Erik Pistol

Given the Laplacian on a planar, convex domain with piecewise linear boundary subject to mixed Dirichlet-Neumann boundary conditions, we provide a sufficient condition for its lowest eigenvalue to dominate the lowest eigenvalue of the…

Spectral Theory · Mathematics 2017-10-03 Jonathan Rohleder

We study the volume growth of metric balls as a function of the radius in discrete spaces, and focus on the relationship between volume growth and discrete curvature. We improve volume growth bounds under a lower bound on the so-called…

Combinatorics · Mathematics 2019-10-15 Brian Benson , Peter Ralli , Prasad Tetali

We derive several upper bounds on the spectral gap of the Laplacian with standard or Dirichlet vertex conditions on compact metric graphs. In particular, we obtain estimates based on the length of a shortest cycle (girth), diameter, total…

Spectral Theory · Mathematics 2023-04-14 Gregory Berkolaiko , James B. Kennedy , Pavel Kurasov , Delio Mugnolo

We consider the Dirichlet Laplacian in a domain two three-dimensional parallel layers having common boundary and coupled by a window. The window produces the bound states below the essential spectrum; we obtain two-sided estimates for them.…

Mathematical Physics · Physics 2007-05-23 Denis Borisov

We investigate the relation between the eigenvalues of the Laplacian with Kirchhoff vertex conditions on a finite metric graph and a corresponding Titchmarsh-Weyl function (a parameter-dependent Neumann-to-Dirichlet map). We give a complete…

Spectral Theory · Mathematics 2018-01-19 Christian Kühn , Jonathan Rohleder

Given a bounded domain $\Omega$ in $\mathbb{R}^N$, $N\geq 1$ we study the asymptotic behavior as $\varepsilon \to 0$ of the eigencurves of $$ -\Delta_p u_\varepsilon=\alpha_\varepsilon m(\tfrac{x}{\varepsilon})(u_\varepsilon^+ )^{p-1} -…

Analysis of PDEs · Mathematics 2016-01-26 Ariel M. Salort

We analyze various formulations of the $\infty$-Laplacian eigenvalue problem on graphs, comparing their properties and highlighting their respective advantages and limitations. First, we investigate the graph $\infty$-eigenpairs arising as…

Spectral Theory · Mathematics 2025-07-16 Piero Deidda , Martin Burger , Mario Putti , Francesco Tudisco

We study the eigenvalues of the Dirichlet Laplace operator on an arbitrary bounded, open set in $\R^d$, $d \geq 2$. In particular, we derive upper bounds on Riesz means of order $\sigma \geq 3/2$, that improve the sharp Berezin inequality…

Spectral Theory · Mathematics 2012-02-29 Leander Geisinger , Ari Laptev , Timo Weidl

The purpose of this article is to establish new lower bounds for the sums of powers of eigenvalues of the Dirichlet fractional Laplacian operator $(-\Delta)^{\alpha/2}|_{\Omega}$ restricted to a bounded domain $\Omega\subset{\mathbb R}^d$…

Analysis of PDEs · Mathematics 2015-01-08 Turkay Yolcu , Selma Yildirim Yolcu

We study the first nonzero Steklov eigenvalue $\lambda_2(T,\delta\Omega)$ of the Dirichlet-to-Neumann operator on a finite tree $T$ with leaf boundary $\delta\Omega$, under a constraint on the diameter $D$. He and Hua [Calc. Var. PDE, 2022]…

Combinatorics · Mathematics 2026-04-15 Jiangdong Ai , Huiqiu Lin , Yongtang Shi

We investigate the asymptotic behavior of the eigenvalues of the Laplacian with homogeneous Robin boundary conditions, when the (positive) Robin parameter is diverging. In this framework, since the convergence of the Robin eigenvalues to…

Analysis of PDEs · Mathematics 2025-07-15 Roberto Ognibene

In this paper, we establish a sharp lower bound for the first Dirichlet eigenvalue of the $p$-Laplacian on bounded domains of a complete, non-compact Riemannian manifold with non-negative Ricci curvature.

Differential Geometry · Mathematics 2026-01-21 Xiaoshang Jin , Zhiwei Lü

In this paper we study eigenvalues of the closed eigenvalue problem of the Witten-Laplacian on an $n$-dimensional compact Riemannian manifold. Estimates for eigenvalues are given. As applications, we give a sharp upper bound for the…

Differential Geometry · Mathematics 2017-01-08 Qing-Ming Cheng , Lingzhong Zeng

The eigenvalue problem for the Laplacian on bounded, planar, convex domains with mixed boundary conditions is considered, where a Dirichlet boundary condition is imposed on a part of the boundary and a Neumann boundary condition on its…

Spectral Theory · Mathematics 2023-01-26 Nausica Aldeghi , Jonathan Rohleder

We consider the problem of geometric optimization of the lowest eigenvalue for the Laplacian on a compact, simply-connected two-dimensional manifold with boundary subject to an attractive Robin boundary condition. We prove that in the…

Spectral Theory · Mathematics 2019-11-14 Magda Khalile , Vladimir Lotoreichik

We prove several results for the Dirichlet, Neumann and Regularity problems for the Laplace equation in graph Lipschitz domains in the plane, considering $A_{\infty}$-measures on the boundary. More specifically, we study the…

Analysis of PDEs · Mathematics 2025-12-30 Fernando Ballesta-Yagüe , María J. Carro

We prove asymptotically optimal upper bounds for the eigenvalues of the Wentzel-Laplace operator on Riemannian manifolds with Ricci curvature bounded below. These bounds depend highly on the geometry of the boundary in addition to the…

Metric Geometry · Mathematics 2020-06-23 Aïssatou M. Ndiaye
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