# Limit points of eigenvalues of truncated unbounded tridiagonal operators

E.K. Ifantis; C.G. Kokologiannaki; E. Petropoulou

Open Mathematics (2007)

- Volume: 5, Issue: 2, page 335-344
- ISSN: 2391-5455

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topE.K. Ifantis, C.G. Kokologiannaki, and E. Petropoulou. "Limit points of eigenvalues of truncated unbounded tridiagonal operators." Open Mathematics 5.2 (2007): 335-344. <http://eudml.org/doc/269763>.

@article{E2007,

abstract = {Let T be a self-adjoint tridiagonal operator in a Hilbert space H with the orthonormal basis \{e n\}n=1∞, σ(T) be the spectrum of T and Λ(T) be the set of all the limit points of eigenvalues of the truncated operator T N. We give sufficient conditions such that the spectrum of T is discrete and σ(T) = Λ(T) and we connect this problem with an old problem in analysis.},

author = {E.K. Ifantis, C.G. Kokologiannaki, E. Petropoulou},

journal = {Open Mathematics},

keywords = {Tridiagonal operators; spectrum; limit points of eigenvalues; orthogonal polynomials; continued fractions; tridiagonal operators},

language = {eng},

number = {2},

pages = {335-344},

title = {Limit points of eigenvalues of truncated unbounded tridiagonal operators},

url = {http://eudml.org/doc/269763},

volume = {5},

year = {2007},

}

TY - JOUR

AU - E.K. Ifantis

AU - C.G. Kokologiannaki

AU - E. Petropoulou

TI - Limit points of eigenvalues of truncated unbounded tridiagonal operators

JO - Open Mathematics

PY - 2007

VL - 5

IS - 2

SP - 335

EP - 344

AB - Let T be a self-adjoint tridiagonal operator in a Hilbert space H with the orthonormal basis {e n}n=1∞, σ(T) be the spectrum of T and Λ(T) be the set of all the limit points of eigenvalues of the truncated operator T N. We give sufficient conditions such that the spectrum of T is discrete and σ(T) = Λ(T) and we connect this problem with an old problem in analysis.

LA - eng

KW - Tridiagonal operators; spectrum; limit points of eigenvalues; orthogonal polynomials; continued fractions; tridiagonal operators

UR - http://eudml.org/doc/269763

ER -

## References

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