Results 121 to 130 of about 2,211 (224)
Rigorous Formulation of the Lasing Eigenvalue Problem as a Spectral Problem for a Fredholm Operator Function [PDF]
, 2018 We propose a new convenient for mathematical investigation formulation of the lasingeigenvalue problem as a spectral problem for an operator-valued function, which involves boundary integral operators.
Karchevskii, Evgenii +2 more
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, 1996 In this paper, we give the representations of Fredholm and semi-Fredholm spectra of multi-Toeplitz operators with symbols inH∞+C, and prove that, for ϕ1,…,ϕn∈H∞+C(n≥2), if (Tϕ1,…,Tϕn) is Fredholm, then ind(Tϕ1,…,Tϕn)=0, in contrast with the case of one ...
Shanli, Sun, Guangfu, Cao
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The time-dependent correlation function of the Jordan-Wigner operator as a Fredholm determinant
, 2009 We calculate a correlation function of the Jordan-Wigner operator in a class of free-fermion models formulated on an infinite one-dimensional lattice. We represent this function in terms of the determinant of an integrable Fredholm operator, convenient ...
Giamarchi, T. +5 more
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Vector valued logarithmic residues and the extraction of elementary factors
An analysis is presented of the circumstances under which, by the extraction of elementary factors, an analytic Banach algebra valued function can be transformed into one taking invertible values only. Elementary factors are generalizations of the simple
Bart, H., Silbermann, B., Ehrhardt, T.
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Perturbation theory for generalized Fredholm operators. II
, 1977 If T is a bounded linear operator with generalized inverse S, i.e. T S T = T TST = T , we obtain conditions so that T − U T - U has a generalized inverse. When
S. R. Caradus
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A fixed-point type result for some non-differentiable Fredholm integral equations
Mathematical Modelling and AnalysisIn this paper, we present a new fixed-point result to draw conclusions about the existence and uniqueness of the solution for a nonlinear Fredholm integral equation of the second kind with non-differentiable Nemytskii operator.
Miguel A. Hernández-Verón +3 more
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Spectral decomposition of a Hilbert space by a Fredholm operator
, 1988 Let T be a Fredholm operator in a Hilbert space H with spectrum σ(T) = {λi}i = 1∞. Let T(λi) = Tλimi, where mi is the ascent of the operator Tλi = λiI − T, and let Pi denote the projection of H onto the generalized eigenspace N (T(γi)) along R (T(γi ...
Lang, Patrick, Locker, John
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Fredholm linear operators associated with ordinary differential equations on noncompact intervals
Electronic Journal of Differential Equations, 1999 In the noncompact interval $J=[a,infty )$ we consider a linear problem of the form $Lx=y,; x in S$, where $L$ is a first order differential operator, $y$ a locally summable function in $J$, and $S$ a subspace of the Fr'{e}chet space of the locally ...
Mariella Cecchi +3 more
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One class of linear Fredholm operator equations of the third kind
, 2020 In this paper, we are applying a new approach to prove that the solution of thelinear Fredholm operator equation of the third kind is equivalent to the solution of the linearFredholm operator equation of the second kind with a certain ...
Matanova, Kalyskan Bazarbaevna +2 more
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Miskolc Mathematical NotesIn this paper, we develop a Legendre wavelets method for the numerical solution of Fredholm-Volterra integro-differential equations of fractional order. The Caputo sense is used to explain the fractional derivative operator.
Marziyeh Felahat
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