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Related papers: Generalized Epsilon-Pseudospectra

200 papers

We study the pseudospectrum of the non-selfadjoint Zakharov-Shabat system in the semiclassical regime. The pseudospectrum may be defined as the union of the spectra of perturbations of the Zakharov-Shabat system, thus it is relevant to the…

Exactly Solvable and Integrable Systems · Physics 2014-02-18 Michael VanValkenburgh

For a given self-adjoint operator $A$ with discrete spectrum, we completely characterize possible eigenvalues of its rank-one perturbations~$B$ and discuss the inverse problem of reconstructing $B$ from its spectrum.

Spectral Theory · Mathematics 2020-07-20 Oles Dobosevych , Rostyslav Hryniv

We address the count of isolated and embedded eigenvalues in a generalized eigenvalue problem defined by two self-adjoint operators with a positive essential spectrum and a finite number of isolated eigenvalues. The generalized eigenvalue…

Dynamical Systems · Mathematics 2007-05-23 M. Chugunova , D. Pelinovsky

The sparse generalized eigenvalue problem arises in a number of standard and modern statistical learning models, including sparse principal component analysis, sparse Fisher discriminant analysis, and sparse canonical correlation analysis.…

Numerical Analysis · Computer Science 2019-03-05 Ganzhao Yuan , Li Shen , Wei-Shi Zheng

Many complex systems can be reduced to their key components through spectrally decomposing matrices that capture their dynamics. These matrices can in turn be constructed from data, often by least-squares fitting: examples of algorithms to…

Numerical Analysis · Mathematics 2026-05-18 Caroline Wormell

It is needed to solve generalized eigenvalue problems (GEP) in many applications, such as the numerical simulation of vibration analysis, quantum mechanics, electronic structure, etc. The subspace iteration is a kind of widely used…

Numerical Analysis · Mathematics 2023-01-02 Biyi Wang , Hengbin An , Hehu Xie , Zeyao Mo

This paper provides the spectral decomposition of $(\star,\epsilon)$-palindromic quadratic matrix polynomial $P(\lambda)$ by a standard pair and a parameter matrix. When $J$ is assumed to be a block diagonal matrix, the parameter matrix…

Numerical Analysis · Mathematics 2026-05-08 Kang Zhao , Xin Wang , Xiaoxiao Ma

We consider the problem of parameter estimation in a high-dimensional generalized linear model. Spectral methods obtained via the principal eigenvector of a suitable data-dependent matrix provide a simple yet surprisingly effective…

Statistics Theory · Mathematics 2025-07-11 Yihan Zhang , Hong Chang Ji , Ramji Venkataramanan , Marco Mondelli

A new approach which generalizes the Selective Modal Analyis (SMA) and algorithms based upon it for solving the generalized eigenvalue problem is described. This approach allows for the systematic consideration of physical properties of the…

Rings and Algebras · Mathematics 2007-05-23 Julian Barquin

We give general spectral and eigenvalue perturbation bounds for a selfadjoint operator perturbed in the sense of the pseudo-Friedrichs extension. We also give several generalisations of the aforementioned extension. The spectral bounds for…

Spectral Theory · Mathematics 2008-01-21 K. Veselic

In the broad range of studies related to quantum graphs, quantum graph spectra appear as a topic of special interest. They are important in the context of diffusion type problems posed on metric graphs. Theoretical findings suggest that…

Numerical Analysis · Mathematics 2023-12-15 Chong-Son Dröge , Anna Weller

In machine learning practice it is often useful to identify relevant input features. Isolating key input elements, ranked according their respective degree of relevance, can help to elaborate on the process of decision making. Here, we…

Machine Learning · Computer Science 2025-11-24 Lorenzo Chicchi , Lorenzo Buffoni , Diego Febbe , Lorenzo Giambagli , Raffaele Marino , Duccio Fanelli

We consider the problem of calculating learning curves (i.e., average generalization performance) of Gaussian processes used for regression. On the basis of a simple expression for the generalization error, in terms of the eigenvalue…

Disordered Systems and Neural Networks · Physics 2007-05-23 Peter Sollich , Anason Halees

Equations arising in General Relativity are usually too complicated to be solved analytically and one has to rely on numerical methods to solve sets of coupled partial differential equations. Among the possible choices, this paper focuses…

General Relativity and Quantum Cosmology · Physics 2016-06-22 Philippe Grandclement , Jérôme Novak

Large-scale eigenvalue problems arise in various fields of science and engineering and demand computationally efficient solutions. In this study, we investigate the subspace approximation for parametric linear eigenvalue problems, aiming to…

We analyze single particle coherence and interference in the presence of particle loss and derive an inequality that relates the preservation of coherence, the creation of superposition with the vacuum, and the degree of particle loss. We…

Quantum Physics · Physics 2007-05-23 Johan Aberg , Daniel K. L. Oi

Parameter estimation connects mathematical models to real-world data and decision making across many scientific and industrial applications. Standard approaches such as maximum likelihood estimation and Markov chain Monte Carlo estimate…

Methodology · Statistics 2026-02-06 Matthew J Simpson , James S Bennett , Alexander Johnston , Ruth E Baker

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

We introduce a simple, general, and convergent scheme to compute generalized eigenfunctions of self-adjoint operators with continuous spectra on rigged Hilbert spaces. Our approach does not require prior knowledge about the eigenfunctions,…

Numerical Analysis · Mathematics 2024-10-14 Matthew J. Colbrook , Andrew Horning , Tianyiwa Xie

In this paper, we extend the original criss-cross algorithms for computing the $\varepsilon$-pseudospectral abscissa and radius to general spectral value sets. By proposing new root-finding-based strategies for the horizontal/radial search…

Optimization and Control · Mathematics 2019-09-09 Peter Benner , Tim Mitchell