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Related papers: Eigenvalue Bounds for Saddle-Point Systems with Si…

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The main focus of this paper is the study of efficient multigrid methods for large linear systems with a particular saddle-point structure. Indeed, when the system matrix is symmetric, but indefinite, the variational convergence theory that…

Numerical Analysis · Mathematics 2023-08-30 Marco Donatelli , Matthias Bolten , Paola Ferrari , Isabella Furci

In this paper we present benchmark problems for non-selfadjoint elliptic eigenvalue problems with large defect and ascent. We describe the derivation of the benchmark problem with a discontinuous coefficient and mixed boundary conditions.…

Numerical Analysis · Mathematics 2019-09-13 Rebekka Gasser , Joscha Gedicke , Stefan Sauter

This paper gives a framework to produce the lower bound of eigenvalues defined in a Hilbert space by the eigenvalues defined in another Hilbert space. The method is based on using the max-min principle for the eigenvalue problems.

Numerical Analysis · Mathematics 2016-09-22 Hehu Xie , Chunguang You

In this paper we are concerned with existence of positive solutions for a Schr\"odinger-Maxwell system with singular or strongly-singular terms. We overcome the difficulty given by the singular terms through an approximation scheme and…

Analysis of PDEs · Mathematics 2021-10-12 Lucio Boccardo , Stefano Buccheri , Carlos Alberto dos Santos

In this paper we present a new bound obtained with the probabilistic method for the solution of the Set Covering problem with unit costs. The bound is valid for problems of fixed dimension, thus extending previous similar asymptotic…

Combinatorics · Mathematics 2014-07-18 Giovanni Felici , Sokol Ndreca , Aldo Procacci , Benedetto Scoppola

We prove sharp upper bounds for eigenvalues of Schr\"odinger operators on quantum graphs with $\delta$-coupling (also known as Robin) conditions at all vertices. The bounds depend on the geometry of the graph, on the potential, and the…

Spectral Theory · Mathematics 2025-05-21 Duc Hoang Cao

A number $\lambda \in \mathbb C $ is called an {\it eigenvalue} of the matrix polynomial $P(z)$ if there exists a nonzero vector $x \in \mathbb C^n$ such that $P(\lambda)x = 0$. Note that each finite eigenvalue of $P(z)$ is a zero of the…

Spectral Theory · Mathematics 2019-02-19 Công-Trình Lê , Thi-Hoa-Binh Du , Tran-Duc Nguyen

In this work, we conduct a systematic study of stochastic saddle point problems (SSP) and stochastic variational inequalities (SVI) under the constraint of $(\epsilon,\delta)$-differential privacy (DP) in both Euclidean and non-Euclidean…

Machine Learning · Computer Science 2024-11-11 Raef Bassily , Cristóbal Guzmán , Michael Menart

This paper studies eigenvalues of the buckling problem of arbitrary order on bounded domains in Euclidean spaces and spheres. We prove universal bounds for the k-th eigenvalue in terms of the lower ones independent of the domains. Our…

Differential Geometry · Mathematics 2010-10-13 Qing-Ming Cheng , Xuerong Qi , Qiaoling Wang , Changyu Xia

This work analyzes singular-value spectra of weight matrices in pretrained transformer models to understand how information is stored at both ends of the spectrum. Using Random Matrix Theory (RMT) as a zero information hypothesis, we…

Machine Learning · Computer Science 2025-11-07 Max Staats , Matthias Thamm , Bernd Rosenow

This paper studies the generalization bounds for the empirical saddle point (ESP) solution to stochastic saddle point (SSP) problems. For SSP with Lipschitz continuous and strongly convex-strongly concave objective functions, we establish…

Optimization and Control · Mathematics 2020-06-04 Junyu Zhang , Mingyi Hong , Mengdi Wang , Shuzhong Zhang

This paper is concerned with singular matrix difference equations of mixed order. The existence and uniqueness of initial value problems for these equations are derived, and then the classification of them is obtained with a similar…

Spectral Theory · Mathematics 2024-11-20 Li Zhu , Huaqing Sun , Bing Xie

We study existence and universality of scaling limits for the eigenvalues of a random normal matrix, in particular at points on the boundary of the spectrum. Our approach uses Ward's equation, which is an identity satisfied by the 1-point…

Probability · Mathematics 2015-10-30 Yacin Ameur , Nam-Gyu Kang , Nikolai Makarov

We develop a new theory for treating boundary problems for linear ordinary differential equations whose fundamental system may have a singularity at one of the two endpoints of the given interval. Our treatment follows an algebraic…

Classical Analysis and ODEs · Mathematics 2015-05-11 M. Rosenkranz , J. Liu , A. Maletzky , B. Buchberger

Randomized block Krylov subspace methods form a powerful class of algorithms for computing the extreme eigenvalues of a symmetric matrix or the extreme singular values of a general matrix. The purpose of this paper is to develop new…

Numerical Analysis · Mathematics 2021-10-05 Joel A. Tropp

In this paper, we study the eigenvalues of the GCD matrix $(S_n)$ and the LCM matrix $[S_n]$ defined on $S_n=\{1,2,\ldots,n\}$. We present upper and lower bounds for the smallest and the largest eigenvalues of $(S_n)$ and $[S_n]$ in terms…

Number Theory · Mathematics 2014-08-15 Ercan Altınışık , Şerife Büyükköse

The eigenvalue bounds obtained earlier [J. Phys. A: Math. Gen. 31 (1998) 963] for smooth transformations of the form V(x) = g(x^2) + f(1/x^2) are extended to N-dimensions. In particular a simple formula is derived which bounds the…

Quantum Physics · Physics 2008-11-26 Richard L. Hall , Nasser Saad

We will study the generalized Steklov Robin eigensystem (with possibly matrices weights) in which the spectral parameter is both in the system and on the boundary. We prove the existence of of an increasing unbounded sequence of eigenvalues…

Analysis of PDEs · Mathematics 2014-11-19 Alzaki Fadlallah

We present a method of cones for rigorous estimations of eigenvectors, eigenspaces and eigenvalues of a matrix. The key notion is the cone-domination and is inspired by ideas from hyperbolic dynamical systems. We present theorems which…

Dynamical Systems · Mathematics 2015-05-20 Łukasz Struski , Jacek Tabor , Piotr Zgliczyński

We state a precise formulation of a conjecture concerning the product of the principal eigenvalue and the sup-norm of the landscape function of the Anderson model restricted to a large box. We first provide the asymptotic of the principal…

Mathematical Physics · Physics 2025-03-24 Daniel Sánchez-Mendoza