Results 71 to 80 of about 1,463 (129)

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  

On the essential spectra of unbounded operator matrices with non diagonal domain and an application

Operators and Matrices, 2019
This paper is devoted to the investigation of the spectral stability of unbounded operator matrices with non diagonal domain in product of Banach spaces.
Marwa Belghith, N. Moalla, I. Walha
semanticscholar   +1 more source

Maps preserving the local spectrum of some matrix products

, 2018
Let Mn(C) denote the algebra of all n×n complex matrices, and x0 a nonzero vector in Cn . For two fixed scalars μ and ν in C for which (μ ,ν) = (0,0) , we characterize all maps φ on Mn(C) satisfying σμST ∗S+νT ∗S(x0) = σμφ(S)φ(T )∗φ(S)+νφ(T )∗φ(S)(x0 ...
Z. Abdelali, Abdelali Achchi, Rabi Marzouki   +2 more
semanticscholar   +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

Local spectral theory of endomorphisms of the disk algebra

Demonstratio Mathematica, 2016
Let A(𝔻) denote the disk algebra. Every endomorphism of A(𝔻) is induced by some ϕ ∈ A(𝔻) with ‖ϕ‖ ≤ 1. In this paper, it is shown that if ϕ is not an automorphism of 𝔻 and ϕ has a fixed point in the open unit disk then the endomorphism induced by ϕ is ...
Trivedi Shailesh, Chandra Harish
doaj   +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
core  

Spectra and fine Spectra of the upper triangular band matrix U(a;0;b) over the sequence space c0

Miskolc Mathematical Notes, 2019
The aim of this paper is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the operator U.aI0Ib/D 266666664 a0 0 b0 0 0 0 0 0 0 0 a1 0 b1 0 0 0 0 0 0 0 a2 0 b2 0 0 0 0 0 0 0 a0 0 b0 0 0 0 0 0 0
N. Durna
semanticscholar   +1 more source

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

An introduction to the distorted Fourier transform

Advanced Nonlinear Studies
This article is intended as an introduction to the distorted Fourier transform associated with a Schrödinger operator on the line or the half-line. This versatile tool has seen numerous applications in nonlinear PDE in recent years.
Ko Haram, Schlag Wilhelm
doaj   +1 more source

Spectra and fine spectra of certain lower triangular double-band matrices as operators on c0

, 2014
In this paper we determine the fine spectrum of the generalized difference operator Δa,b defined by a lower triangular double-band matrix over the sequence space c0.
S. El-Shabrawy
semanticscholar   +1 more source