Results 51 to 60 of about 1,201 (92)

Additive spectra of the 1/4 Cantor measure [PDF]

, 2013
In this paper, we add to the characterization of the Fourier spectra for Bernoulli convolution measures. These measures are supported on Cantor subsets of the line.
Jorgensen, Palle E. T., Kornelson, Keri A., Shuman, Karen L.   +2 more
core  

The Resolvent of Impulsive Singular Hahn–Sturm–Liouville Operators

Annales Mathematicae Silesianae
In this study, the resolvent of the impulsive singular Hahn–Sturm– Liouville operator is considered. An integral representation for the resolvent of this operator is obtained.
Allahverdiev Bilender P., Tuna Hüseyin, Isayev Hamlet A.   +2 more
doaj   +1 more source

Joint numerical ranges: recent advances and applications minicourse by V. Müller and Yu. Tomilov

Concrete Operators, 2020
We present a survey of some recent results concerning joint numerical ranges of n-tuples of Hilbert space operators, accompanied with several new observations and remarks.
Müller V., Tomilov Yu.
doaj   +1 more source

Taylor spectrum and characteristic functions of commuting 2-contractions [PDF]

, 2007
In this work, we give a description of Taylor spectrum of commuting 2- contractions in terms of characteristic functions of such contractions.The case of a single obtained by B.Sz.Nagy and C.
Bendoukha, Berrabah
core   +1 more source

Essential spectrum of a fermionic quantum field model

, 2014
An interaction system of a fermionic quantum field is considered. The state space is defined by a tensor product space of a fermion Fock space and a Hilbert space. It is assumed that the total Hamiltonian is a self-adjoint operator on the state space and
Takaesu, Toshimitsu
core   +1 more source

Spectral isometries on non-simple C*-algebras [PDF]

, 2011
We prove that unital surjective spectral isometries on certain non-simple unital C*-algebras are Jordan isomorphisms. Along the way, we establish several general facts in the setting of semisimple Banach algebras.Comment: 7 pages; paper available since ...
Ahmed, Martin Mathieu, R. Sourour
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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
doaj   +1 more source

Generalized Derivations and Norm Equality in Normed Ideals [PDF]

, 2011
2000 Mathematics Subject Classification: 47A10, 47A12, 47A30, 47B10, 47B20, 47B37, 47B47, 47D50.We compare the norm of a generalized derivation on a Hilbert space with the norm of its restrictions to Schatten norm ...
Barraa, Mohamed
core  

On powers of operators with spectrum in cantor sets and spectral synthesis

, 2017
For $\xi \in \big( 0, \frac{1}{2} \big)$, let $E_{\xi}$ be the perfect symmetric set associated with $\xi$, that is $$E_{\xi} = \Big\{ \exp \Big( 2i \pi (1-\xi) \sum_{n = 1}^{+\infty} \epsilon_{n} \xi^{n-1} \Big) : \, \epsilon_{n} = 0 \textrm{ or } 1 ...
Zarrabi, Mohamed
core   +1 more source

Ultrametric Fredholm operators and approximate pseudospectrum [PDF]

Arab Journal of Mathematical Sciences
PurposeThe paper deals with ultrametric bounded Fredholm operators and approximate pseudospectra of closed and densely defined (resp. bounded) linear operators on ultrametric Banach spaces.Design/methodology/approachThe author used the notions of ...
Jawad Ettayb
doaj   +1 more source