Results 21 to 30 of about 2,211 (224)
Bibechana, 2012 The Fredholm Alternative Theorem gives the notion of bounded and continuous operator which makes a family F of elements of C[a, b] bounded and equicontinuous. A continuous operator of finite rank is completely continuous but every continuous operator is
GK Palei, NP Sah
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On the quasi-Fredholm and Saphar spectrum of strongly continuous Cosine operator function
Moroccan Journal of Pure and Applied Analysis, 2021 Let (C(t))t∈ be a strongly continuous cosine family and A be its infinitesimal generator. In this work, we prove that, if C(t) – coshλt is Saphar (resp. quasi-Fredholm) operator and λt /∉iπ, then A – λ2 is also Saphar (resp.
Boua Hamid
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Algorithms, 2023 Integro-differential equations involving Volterra and Fredholm operators (VFIDEs) are used to model many phenomena in science and engineering. Nonlocal boundary conditions are more effective, and in some cases necessary, because they are more accurate ...
Efthimios Providas +1 more
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Fredholm Operators: A Counterexample [PDF]
Proceedings of the American Mathematical Society, 1969 In 1960 Pietsch [I] gave an example of a locally convex linear topological space for which the set of Fredholm operators is not open. It is the purpose of this note to show that the Fredholm class is not open for any weak locally convex space. A Hausdorff locally convex space is called a weak locally convex space if every null-neighborhood contains a ...
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Elliptic operators and their symbols
Demonstratio Mathematica, 2019 We consider special elliptic operators in functional spaces on manifolds with a boundary which has some singular points. Such an operator can be represented by a sum of operators, and for a Fredholm property of an initial operator one needs a Fredholm ...
Vasilyev Vladimir
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Вестник КазНУ. Серия математика, механика, информатика, 2021 In this paper we consider the properties of the resolvent of a linear operator corresponding to a degenerate singular second-order differential equation with variable coefficients, considered in the Lebesgue space.
K. N. Ospanov, A. N. Yesbayev
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Fredholm factorization of Wiener-Hopf scalar and matrix kernels [PDF]
, 2007 A general theory to factorize the Wiener-Hopf (W-H) kernel using Fredholm Integral Equations (FIE) of the second kind is presented. This technique, hereafter called Fredholm factorization, factorizes the W-H kernel using simple numerical quadrature.
V. Daniele +3 more
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Fredholm operators on C*-algebras [PDF]
Acta Scientiarum Mathematicarum, 2017 The aim of this note is to generalize the notion of Fredholm operator to an arbitrary $C^*$-algebra. Namely, we define "finite type" elements in an axiomatic way, and also we define Fredholm type element $a$ as such element of a given $C^*$-algebra for which there are finite type elements $p$ and $q$ such that $(1-q)a(1-p)$ is "invertible".
Kečkić, Dragoljub J., Lazović, Zlatko
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Известия Иркутского государственного университета: Серия "Математика", 2020 The paper considers a new approach to constructing generalized solutions of degenerate integro-differential equations convolution type in Banach spaces.
M.V. Falaleev
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$C_{0}$-Fredholm operators. IV [PDF]
Publicacions Matemàtiques, 1983 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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