Results 21 to 30 of about 60,735 (247)
, 2016 We recall criteria on the spectrum of Jacobi matrices such that the corresponding isospectral torus consists of periodic operators. Motivated by those known results for Jacobi matrices, we define a new class of operators called GMP matrices.
Eichinger, Benjamin
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Reflectionless Herglotz Functions and Jacobi Matrices [PDF]
Communications in Mathematical Physics, 2008 A measure \(\mu\) on \(\mathbb R\) is said to be reflectionless on a compact set \(E \subset \mathbb R\) if its Stieltjes transform has purely imaginary boundary values almost everywhere on \(E\). If the set \(E\) is homogeneous, that is, there is \(\epsilon>0\) such that \(|E\cap(x-h,x+h)|>\epsilon h\) for all \(x\in E\) and \(h\in(0,\text{diam }E]\),
Poltoratski, Alexei, Remling, Christian
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A Comparison of Sequential and GPU Implementations of Iterative Methods to Compute Reachability Probabilities [PDF]
Electronic Proceedings in Theoretical Computer Science, 2012 We consider the problem of computing reachability probabilities: given a Markov chain, an initial state of the Markov chain, and a set of goal states of the Markov chain, what is the probability of reaching any of the goal states from the initial state ...
Elise Cormie-Bowins
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Sum Rules for Jacobi Matrices and Their Applications to Spectral Theory [PDF]
, 2003 We discuss the proof of and systematic application of Case's sum rules for Jacobi matrices. Of special interest is a linear combination of two of his sum rules which has strictly positive terms.
Killip, Rowan, Simon, Barry
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Spectral Estimates for Periodic Jacobi Matrices [PDF]
Communications in Mathematical Physics, 2003 We obtain bounds for the spectrum and for the total width of the spectral gaps for Jacobi matrices on $\ell^2(\Z)$ of the form $(H )_n= a_{n-1} _{n-1}+b_n _n+a_n _{n+1}$, where $a_n=a_{n+q}$ and $b_n=b_{n+q}$ are periodic sequences of real numbers. The results are based on a study of the quasimomentum $k(z)$ corresponding to $H$. We consider $k(z)$
Korotyaev, Evgeni, Krasovsky, Igor V.
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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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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 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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Inhomogeneous Jacobi Matrices on Trees [PDF]
Constructive Approximation, 2018 We study Jacobi matrices on trees with one end at inifinity. We show that the defect indices cannot be greater than 1 and give criteria for essential selfadjointness. We construct certain polynomials associated with matrices, which mimic orthogonal polynomials in the classical case. Nonnegativity of Jacobi matrices is studied as well.
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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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