Results 31 to 40 of about 100 (42)

A new Browder type property

, 2020
In this paper, a new class of operators (Jbv) satisfying a new spectral property (Bv) of Browder type is defined. This property is shown to be stronger than the Browder type properties (az), (ah), (Sab), (Sb), (VΠ), (VΠa) and Weyl type properties (z), (v)
N. Jayanthi, P. Vasanthakumar
semanticscholar   +1 more source

Stability of essential spectra of closed operators under T-compact equivalence and applications

SERIES III - MATEMATICS, INFORMATICS, PHYSICS, 2019
The main subject of this paper is to introduce and study the concept of T -compact equivalence of closed linear operators in Hilbert spaces. Many results are proved via this equivalence, especially the invariance of essential spectra of T -compact ...
N. Khaldi, B. Messirdi
semanticscholar   +1 more source

On Some Properties of Spectra and Essential Spectra in Banach Spaces

Sarajevo Journal of Mathematics
In this paper, we study diverse properties satisfied by the spectra, Wolf and Weyl essential spectra of bounded linear operators and their links with the structures of Banach spaces.   2010 Mathematics Subject Classification.
Abdelkader Dehici
semanticscholar   +1 more source

Some properties of the essential numerical range on Banach spaces

, 2017
We study the properties of the essential algebraic numerical range as well as the essential spatial numerical range for Banach space operators.
L. Muhati, J. Bonyo, J. O. Agure
semanticscholar   +1 more source

Perturbating Upper Semi-fredholm With Strictly Singular Operators

Sarajevo Journal of Mathematics
Given an upper semi-Fredholm operator $L$, following the work of P. Cassaza and N. Kalton [1] and others, we introduce and study a set of upper semi-Fredholm operators having the same index as $L$ and which is invariant under strictly singular ...
Fernando Galaz-Fontes
semanticscholar   +1 more source

Weyl's theorem and property (Saw)

, 2018
In [8], Sanabria et al. have shown that Weyl’s theorem holds for operators satisfying property(Saw). In this paper, it is shown that its converse is not true with examples and the required condition is derived.
N. Jayanthi
semanticscholar   +1 more source

Some Results in Fredholm Theory via The Measure of Noncompactness

, 2015
Let A be a bounded linear operator in a complex Banach space X. We show that IdX A is a Fredholm operator provided that A has a suciently small polynomially measure of noncompactness.
Saoudi Khaled, Hitta Amara
semanticscholar   +1 more source

Variations on Weyl type theorems

, 2013
In this paper we introduce and study two new properties (Bb) and (Bab) in connection with Weyl type theorems. It is shown that if T is a bounded linear operator acting on a Banach space X, then property (Bb) holds for T if and only if generalized Browder’
A. Gupta, N. Kashyap
semanticscholar   +1 more source

Optimal Regularity and Fredholm Properties of Abstract Parabolic Operators in Lp Spaces on the Real Line

, 2005
D. D. Giorgio, A. Lunardi, R. Schnaubelt
semanticscholar   +1 more source

Toeplitz Operators with Symbols Generated by Slowly Oscillating and Semi‐Almost Periodic Matrix Functions

, 2004
M. A. Bastos, Y. Karlovich, B. Silbermann   +2 more
semanticscholar   +1 more source