Results 41 to 50 of about 808,768 (351)
EIGENVALUE COLLISION FOR PT-SYMMETRIC WAVEGUIDE
Acta Polytechnica, 2014 We consider a model of a planar PT-symmetric waveguide and study the phenomenon of the eigenvalue collision under perturbation of the boundary conditions. This phenomenon was discovered numerically in previous works.
Denis Borisov
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Relative perturbation theory for diagonally dominant matrices [PDF]
, 2014 In this paper, strong relative perturbation bounds are developed for a number of linear algebra problems involving diagonally dominant matrices. The key point is to parameterize diagonally dominant matrices using their off-diagonal entries and diagonally
Dailey, Megan +2 more
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Eigenvalues, pseudospectrum and structured perturbations [PDF]
Linear Algebra and its Applications, 2006 AbstractWe investigate the behavior of eigenvalues under structured perturbations. We show that for many common structures such as (complex) symmetric, Toeplitz, symmetric Toeplitz, circulant and others the structured condition number is equal to the unstructured condition number for normwise perturbations, and prove similar results for real ...
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On the Perturbed Eigenvalue Problem
Journal of Mathematical Analysis and Applications, 1995 AbstractThe perturbed eigenvalue problem L(x)v(x) = λ(x)v(x) is considered near 0 = x ∈ R with L(x) a Fredholm operator of index zero. Using the Implicit Function Theorem and the Bordering Lemma, a necessary and sufficient smoothness condition is derived for the characteristic pairs (λ(x), υ(x)) with eigenvalue λ(x) emanating from a semi-simple ...
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Analysis of alpha modes in multigroup diffusion
Nuclear Engineering and Technology, 2017 The alpha eigenvalue problem in multigroup neutron diffusion is studied with particular attention to the theoretical analysis of the model. Contrary to previous literature results, the existence of eigenvalue and eigenflux clustering is investigated here
Richard Sanchez +3 more
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ASM Science Journal, 2022 This work is aimed at obtaining the energy eigenvalues for one-dimensional quantum harmonic and anharmonic oscillators perturbed by linear, quadratic, cubic and polynomial potentials.
B.I Madububa +4 more
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An approximate diagonalization method for large scale Hamiltonians
, 2012 An approximate diagonalization method is proposed that combines exact diagonalization and perturbation expansion to calculate low energy eigenvalues and eigenfunctions of a Hamiltonian.
Amin, Mohammad H. +3 more
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On condition numbers of polynomial eigenvalue problems with nonsingular leading coefficients [PDF]
, 2008 In this paper, we investigate condition numbers of eigenvalue problems of matrix polynomials with nonsingular leading coefficients, generalizing classical results of matrix perturbation theory.
Papathanasiou, Nikolaos +1 more
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Positive solutions for perturbations of the Robin eigenvalue problem plus an indefinite potential
, 2019 We study perturbations of the eigenvalue problem for the negative Laplacian plus an indefinite and unbounded potential and Robin boundary condition. First we consider the case of a sublinear perturbation and then of a superlinear perturbation.
Papageorgiou, N. S. +2 more
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Perturbing eigenvalues of nonnegative matrices
Linear Algebra and its Applications, 2016 Let $A$ be an irreducible (entrywise) nonnegative $n\times n$ matrix with eigenvalues $$ , b+ic,b-ic, _4,\cdots, _n,$$ where $ $ is the Perron eigenvalue. It is shown that for any $t \in [0, \infty)$ there is a nonnegative matrix with eigenvalues $$ + \tilde t, _2+t, _3+t, _4 \cdots, _n,$$ whenever $\tilde t \ge _n t$ with $ _3=1, _4 ...
Xuefeng Wang +2 more
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