Results 11 to 20 of about 35 (35)

Intrinsic characterizations of perturbation classes on some Banach spaces

, 2010
We investigate relationships between inessential operators and improjective operators acting between Banach spaces X and Y, emphasizing the case in which one of the spaces is a C(K) space.
Gonzalez, M., AIENA, Pietro
core   +1 more source

The basic propositions on defect numbers, root numbers and indices of linear operators [PDF]

, 2020
: In this work, we use the notion of the measure of noncompactness in order to establish some results concerning the class of semi-Fredholm and Fredholm operators.
Weidmann, ; J 47b07. ; K. Astala, E Daneš ; D, C Evans ; I, M G Gohberg, 47a55, ; K Goldberg, 47a10, K Banaś, 47a53, ; S Kreǐn, W D Edmunds, ; J Geobel, J Gustafson   +13 more
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EP Elements in Rings and in Semigroups with Involution and in C*-algebras [PDF]

, 2015
This work includes a survey of most of the results concerning EP elements in semigroups and rings with involution and in C*-algebras. 2010 Mathematics Subject Classification: Primary 46L05, 46J05, 46H05, 46H30, 47A05, 47A53, 47A60, 15A09, 15A33, 16A28 ...
Karanasios, Sotirios
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FREDHOLM AND PROPERNESS PROPERTIES OF QUASILINEAR ELLIPTIC SYSTEMS OF SECOND ORDER [PDF]

, 2017
For a large class of subsets $\varOmega\subset\mathbb{R}^{N}$ (including unbounded domains), we discuss the Fredholm and properness properties of second-order quasilinear elliptic operators viewed as mappings from $W^{2,p}(\varOmega;\mathbb{R}^{m})$ to ...
Gebran, Hicham G., Stuart, Charles A.
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Characterization and stability of essential pseudospectra by measure of polynomially inessential operators [PDF]

  In this article, we investigate the essential pseudospectra through the framework of polynomially inessential operators, which extends the class of polynomially strictly singular operators and provides a broader setting for Fredholm-type ...
ELGABEUR, Bilel
core   +2 more sources

Certain properties of the essential spectra in Banach spaces [PDF]

, 2017
Paper presented at the 4th Strathmore International Mathematics Conference (SIMC 2017), 19 - 23 June 2017, Strathmore University, Nairobi, Kenya.Let X be an arbitrary Banach space, and L (X) be the set of all bounded linear operators on X.
Agure, J. O., Muhati, L. N., Bonyo, J. O.   +2 more
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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 Id X − A is a Fredholm operator provided that A has a sufficiently small polynomially measure of noncompactness.
Saoudi Khaled
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© Hindawi Publishing Corp. REMARKS ON EMBEDDABLE SEMIGROUPS IN GROUPS AND A GENERALIZATION OF SOME CUTHBERT’S RESULTS

, 2001
Let (U(t))t≥0 be a C0-semigroup of bounded linear operators on a Banach space X. In this paper, we establish that if, for some t0> 0, U(t0) is a Fredholm (resp., semi-Fredholm) operator, then (U(t))t≥0 is a Fredholm (resp., semi-Fredholm) semi-group ...
Khalid Latrach, Abdelkader Dehici
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Multivalued linear projections

, 2004
A multivalued linear projection operator P defined on linear space X is a multivalued linear operator which is idempotent and has invariant domain. We show that a multivalued projection can be characterized in terms of a pair of subspaces and then ...
Cross, RW, Wilcox, DL
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A note on the essential pseudospectra and application

Linear and Multilinear Algebra, 2016
Aref Jeribi, Ammar Aymen
exaly