Results 11 to 20 of about 500,170 (139)
On the completely indeterminate case for block Jacobi matrices
Concrete Operators, 2017 We consider the infinite Jacobi block matrices in the completely indeterminate case, i. e. such that the deficiency indices of the corresponding Jacobi operators are maximal.
Osipov Andrey
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Darboux transformation of symmetric Jacobi matrices and Toda lattices [PDF]
Frontiers in Applied Mathematics and StatisticsLet J be a symmetric Jacobi matrix associated with some Toda lattice. We find conditions for Jacobi matrix J to admit factorization J = LU (or J = 𝔘𝔏) with L (or 𝔏) and U (or 𝔘) being lower and upper triangular two-diagonal matrices, respectively.
Ivan Kovalyov, Oleksandra Levina
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On Fourier Series in the Context of Jacobi Matrices
AxiomsWe investigate the properties of matrices that emerge from the application of Fourier series to Jacobi matrices. Specifically, we focus on functions defined by the coefficients of a Fourier series expressed in orthogonal polynomials.
José M. A. Matos +2 more
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Jacobi matrices with lacunary spectrum [PDF]
, 2020 We find asymptotics of entries of Jacobi matrices with lacunary spectral data under some additional growth conditions. We also prove the inverse results.
Losev, Ilya
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Computing the Hessenberg matrix associated with a self-similar measure [PDF]
, 2011 We introduce in this paper a method to calculate the Hessenberg matrix of a sum of measures from the Hessenberg matrices of the component measures. Our method extends the spectral techniques used by G.
Giraldo Carbajo, Antonio +3 more
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On a Discrete Inverse Problem for Two Spectra
Discrete Dynamics in Nature and Society, 2012 A version of the inverse spectral problem for two spectra of finite-order real Jacobi matrices (tridiagonal symmetric matrices) is investigated. The problem is to reconstruct the matrix using two sets of eigenvalues: one for the original Jacobi matrix ...
Gusein Sh. Guseinov
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Relaxation parameters and composite refinement techniques
Results in Applied Mathematics, 2022 A composite refinement technique for two stationary iterative methods, one of them contains a relaxation parameter, is introduced. Four new techniques, Jacobi successive over relaxation (SOR) composite refinement (RJSOR), SOR Jacobi composite refinement (
Sh.A. Meligy, I.K. Youssef
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On unbounded commuting Jacobi operators and some related issues
Concrete Operators, 2019 We consider the situations, when two unbounded operators generated by infinite Jacobi matrices, are self-adjoint and commute. It is found that if two Jacobi matrices formally commute, then two corresponding operators are either self-adjoint and commute ...
Osipov Andrey
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Block Jacobi matrices and Titchmarsh-Weyl function [PDF]
Opuscula MathematicaWe collect some results and notions concerning generalizations for block Jacobi matrices of several concepts, which have been important for spectral studies of the simpler and better known scalar Jacobi case.
Marcin Moszyński, Grzegorz Świderski
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Results in Applied Mathematics, 2019 The optimal Jacobi parameter (ω) in Jacobi's iterative method is obtained for specific classes of matrices. We define ωopt as the worst-case optimal parameter.
Gregory J. Kimmel, Andreas Glatz
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