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Related papers: Variations of Ritz and Lehmann Bounds

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The creation and justification of the methods for minimax estimation of parameters of the external boundary value problems for the Helmholtz equation in unbounded domains are considered. When observations are distributed in subdomains, the…

Analysis of PDEs · Mathematics 2009-10-14 Yury Podlipenko , Yury Shestopalov , Vladimir Prishlyak

We consider the problem of deriving upper bounds on the parameters of sum-rank-metric codes, with focus on their dimension and block length. The sum-rank metric is a combination of the Hamming and the rank metric, and most of the available…

Combinatorics · Mathematics 2023-10-30 Aida Abiad , Antonina P. Khramova , Alberto Ravagnani

This book is about solving matrix nearness problems that are related to eigenvalues or singular values or pseudospectra. These problems arise in great diversity in various fields, be they related to dynamics, as in questions of robust…

Numerical Analysis · Mathematics 2025-07-29 Nicola Guglielmi , Christian Lubich

Variance parameter estimation in linear mixed models is a challenge for many classical nonlinear optimization algorithms due to the positive-definiteness constraint of the random effects covariance matrix. We take a completely novel view on…

Machine Learning · Statistics 2022-12-20 Lena Sembach , Jan Pablo Burgard , Volker H. Schulz

In this note we present upper bounds for the variational eigenvalues of the $p$-Laplacian on smooth domains of complete $n$-dimensional Riemannian manifolds and Neumann boundary conditions, and on compact (boundaryless) Riemannian…

Spectral Theory · Mathematics 2021-09-17 Bruno Colbois , Luigi Provenzano

A simple and efficient variational method is introduced to accelerate the convergence of the eigenenergy computations for a Hamiltonian H with singular potentials. Closed-form analytic expressions in N dimensions are obtained for the matrix…

Mathematical Physics · Physics 2009-11-10 Nasser Saad , Richard L. Hall , Qutaibeh D. Katatbeh

In this paper, we obtain the bounds of the extreme eigenvalues of a normalized and signless Laplacian matrices using by their traces. In addition, we determine the bounds for k-th eigenvalues of normalized and signless Laplacian matrices.

Combinatorics · Mathematics 2014-09-01 Şerife Büyükköse , Şehri Gülčiček Eski

The product of a Hermitian matrix and a positive semidefinite matrix has only real eigenvalues. We present bounds for sums of eigenvalues of such a product.

Functional Analysis · Mathematics 2019-05-13 Bo-Yan Xi , Fuzhen Zhang

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

When an eigenvector of a semi-bounded operator is positive, we show that a remarkably simple argument allows to obtain upper and lower bounds for its associated eigenvalue. This theorem is a substantial generalization of Barta-like…

Spectral Theory · Mathematics 2009-11-11 Amaury Mouchet

We show how positive unital linear maps can be used to obtain lower bounds for the maximum distance between the eigenvalues of two normal matrices. Some related bounds for the spread and condition number of Hermitian matrices are also…

Functional Analysis · Mathematics 2015-09-21 R. Sharma , R. Kumari

The Rayleigh-Ritz (RR) method finds the stationary values, called Ritz values, of the Rayleigh quotient on a given trial subspace as approximations to eigenvalues of a Hermitian operator $A$. If the trial subspace is $A$-invariant, the Ritz…

Numerical Analysis · Mathematics 2010-01-08 Andrew V. Knyazev , Merico E. Argentati

To provide mathematically rigorous eigenvalue bounds for the Steklov eigenvalue problem, an enhanced version of the eigenvalue estimation algorithm developed by the third author is proposed, which removes the requirements of the positive…

Numerical Analysis · Mathematics 2018-08-27 Chun'guang You , Hehu Xie , Xuefeng Liu

An algorithm named EigenWave is described to compute eigenvalues and eigenvectors of elliptic boundary value problems. The algorithm, based on the recently developed WaveHoltz scheme, solves a related time-dependent wave equation as part of…

Numerical Analysis · Mathematics 2025-07-25 Daniel Appelo , Jeffrey W. Banks , William D. Henshaw , Ngan Le , Donald W. Schwendeman

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

We present a new approach to compute selected eigenvalues and eigenvectors of the two-parameter eigenvalue problem. Our method requires computing generalized eigenvalue problems of the same size as the matrices of the initial two-parameter…

Numerical Analysis · Mathematics 2021-05-12 Henrik Eisenmann , Yuji Nakatsukasa

Many fields of science and engineering require finding eigenvalues and eigenvectors of large matrices. The solutions can represent oscillatory modes of a bridge, a violin, the disposition of electrons around an atom or molecule, the…

Quantum Physics · Physics 2008-06-10 Eric J. Heller , Lev Kaplan , Frank Pollmann

One main issue, when numerically integrating autonomous Hamiltonian systems, is the long-term conservation of some of its invariants, among which the Hamiltonian function itself. Recently, a new class of methods, named "Hamiltonian Boundary…

Numerical Analysis · Mathematics 2010-02-09 Luigi Brugnano , Felice Iavernaro , Donato Trigiante

In this paper, we investigate eigenvalues of the Wentzel-Laplace operator on a bounded domain in some Riemannian manifold. We prove asymptotically optimal estimates, according to the Weyl's law through bounds that are given in terms of the…

Metric Geometry · Mathematics 2020-05-27 Aïssatou M. Ndiaye

A method to generate new classes of random matrix ensembles is proposed. Random matrices from these ensembles are Lax matrices of classically integrable systems with a certain distribution of momenta and coordinates. The existence of an…

Chaotic Dynamics · Physics 2011-09-26 E. Bogomolny , O. Giraud , C. Schmit
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