Zobrazeno 1 - 9
of 9
pro vyhledávání: '"Maria Malejki"'
Autor:
Maria Malejki
Publikováno v:
Opuscula Mathematica, Vol 41, Iss 6, Pp 861-879 (2021)
Under suitable assumptions the eigenvalues for an unbounded discrete operator \(A\) in \(l_2\), given by an infinite complex band-type matrix, are approximated by the eigenvalues of its orthogonal truncations. Let \[\Lambda (A)=\{\lambda \in {\rm Lim
Externí odkaz:
https://doaj.org/article/352e3db55dc74e42a73b119562036eb7
Autor:
Maria Malejki
Publikováno v:
Opuscula Mathematica, Vol 34, Iss 1, Pp 139-160 (2014)
The spectral properties and the asymptotic behaviour of the discrete spectrum for a special class of infinite tridiagonal matrices are given. We derive the asymptotic formulae for eigenvalues of unbounded complex Jacobi matrices acting in \(l^2(\math
Externí odkaz:
https://doaj.org/article/40b565db464a4355ab37fe378d4e44c5
Autor:
Maria Malejki
Publikováno v:
Opuscula Mathematica, Vol 30, Iss 3, Pp 311-330 (2010)
The research included in the paper concerns a class of symmetric block Jacobi matrices. The problem of the approximation of eigenvalues for a class of a self-adjoint unbounded operators is considered. We estimate the joint error of approximation for
Externí odkaz:
https://doaj.org/article/1acdfadecfe144ba89a4975328140c54
Autor:
Maria Malejki
Publikováno v:
Opuscula Mathematica, Vol 27, Iss 1, Pp 37-49 (2007)
We investigate the problem of approximation of eigenvalues of some self-adjoint operator in the Hilbert space \(l^2(\mathbb{N})\) by eigenvalues of suitably chosen principal finite submatrices of an infinite Jacobi matrix that defines the operator co
Externí odkaz:
https://doaj.org/article/25473aa8b9904777ba0e5895f740a437
Autor:
Maria Malejki
Publikováno v:
Journal of Advances in Mathematics and Computer Science. 26:1-9
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f94f79972ccf206c8308f1a072633416
https://doi.org/10.9734/jamcs/2018/39654
https://doi.org/10.9734/jamcs/2018/39654
Autor:
Maria Malejki
Publikováno v:
Open Mathematics, Vol 8, Iss 1, Pp 114-128 (2010)
We consider the problem of approximation of eigenvalues of a self-adjoint operator J defined by a Jacobi matrix in the Hilbert space l 2(ℕ) by eigenvalues of principal finite submatrices of an infinite Jacobi matrix that defines this operator. We a
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d6fb2a84249a3bd83cb28e5e5954ea47
https://doi.org/10.2478/s11533-009-0064-x
https://doi.org/10.2478/s11533-009-0064-x
Autor:
Maria Malejki
Publikováno v:
Linear Algebra and its Applications. 431:1952-1970
The aim of this paper is to find asymptotic formulas for eigenvalues of self-adjoint discrete operators in l 2 ( N ) given by some infinite symmetric Jacobi matrices. The approach used to calculate an asymptotic behaviour of eigenvalues is based on m
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3aa6b1746cbf87b79b8711393c4da52f
https://doi.org/10.1016/j.laa.2009.06.035
https://doi.org/10.1016/j.laa.2009.06.035
Autor:
Jan Janas, Maria Malejki
Publikováno v:
Journal of Computational and Applied Mathematics. 200:342-356
In this article we calculate the asymptotic behaviour of the point spectrum for some special self-adjoint unbounded Jacobi operators J acting in the Hilbert space l^2=l^2(N). For given sequences of positive numbers @l"n and real q"n the Jacobi operat
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d742ba80b4db04a1804762566ffec62d
https://doi.org/10.1016/j.cam.2005.09.033
https://doi.org/10.1016/j.cam.2005.09.033
Publikováno v:
Proceedings of the Edinburgh Mathematical Society. 46:575-595
In this paper spectral properties of non-selfadjoint Jacobi operators $J$ which are compact perturbations of the operator $J_0=S+\rho S^*$, where $\rho\in(0,1)$ and $S$ is the unilateral shift operator in $\ell^2$, are studied. In the case where $J-J
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::bcec63737d709fcd335e6997227bfe9c
https://doi.org/10.1017/s0013091502000925
https://doi.org/10.1017/s0013091502000925