Results 81 to 90 of about 500,094 (203)

Fredholm Operators and Spectral Flow [PDF]

, 2016
These are extended lecture notes of a PhD course that the author gave at the Universita degli studi di Torino in Italy in spring 2013.
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Bifurcation theory for Fredholm operators

Journal of Differential Equations
This paper consists of four parts. It begins by using the authors's generalized Schauder formula, [50], and the algebraic multiplicity, $χ$, of Esquinas and López-Gómez [18,17,40] to package and sharpening all existing results in local and global bifurcation theory for Fredholm operators through the recent author's axiomatization of the Fitzpatrick ...
Julián López-Gómez, Juan Carlos Sampedro   +1 more
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Closed Fredholm and semi-Fredholm operators, essential spectra and perturbations [PDF]

, 1975
In these notes we provide rather extensive characterizations of closed densely defined Fredholm and semi-Fredholm operators on a Banach space, and their perturbation classes.
Williams, Vernon
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Fredholm composition operators [PDF]

Proceedings of the American Mathematical Society, 1997
Fredholm composition operators on a variety of Hilbert spaces of analytic functions on domains in C N
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A note on the decomposition of Fredholm operators

Demonstratio Mathematica, 2008
AbstractWe generalize a result of F. Szigeti concerning the decomposition of Fredholm operators on Banach spaces.
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Some New Properties in Fredholm Theory, Schechter Essential Spectrum, and Application to Transport Theory

Journal of Inequalities and Applications, 2008
The theory of measures of noncompactness has many applications on topology, functional analysis, and operator theory. In this paper, we consider one axiomatic approach to this notion which includes the most important classical definitions.
Dehici Abdelkader, Abdelmoumen Boulbeba, Jeribi Aref, Mnif Maher   +3 more
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Index of Fredholm operators [PDF]

Proceedings of the American Mathematical Society, 1973
Let X, Y, Z be Banach spaces, and let T:X-.Y and S: Y-*Z be Fredholm operators. Let ind(T) denote the index of T. A short proof is given for the identity ind(ST)=ind(S)+ind(T). We give a "one-diagram" proof of the following theorem [3, Theorem 3, p. 121]. The notation of [3] will be used. THEOREM. Let X, Y, Z be Banach spaces, and T: X-?
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The Spectral Property (ωπ): Equivalent Operators in Functionals, Families of Operators, and Tensor Products

Mathematics
The spectral property (ωπ) generalizes the a-Weyl theorem and characterizes the relationships between the spectrum and the upper semi-Fredholm spectrum.
Elvis Aponte, Ennis Rosas
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Interpolation of Fredholm operators

Advances in Mathematics, 2016
We prove novel results on interpolation of Fredholm operators including an abstract factorization theorem. The main result of this paper provides sufficient conditions on the parameters $θ\in (0,1)$ and $q\in \lbrack 1,\infty ]$ under which an operator $A$ is a Fredholm operator from the real interpolation space $(X_{0},X_{1})_{θ,q}$ to $(Y_{0},Y_{1})_{
Asekritova, I., Kruglyak, N., Mastyło, M.   +2 more
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On Semi-Fredholm Operators [PDF]

, 1992
VIe prove that every semi-Fredholm operator on a.n arbitrary Banach space can be approxima.ted by injective or surjective operators. In the case of a complex separable Hilbert space, we show that the set of semi-Fredholm operators having a fixed index is
FERNANDO GALAZ FONTES
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