Results 1 to 10 of about 3,224 (219)
Singularly perturbed rank one linear operators
Математичні Студії, 2021 The basic principles of the theory of singularly perturbed self-adjoint operators are generalized to the case of closed linear operators with non-symmetric perturbation of rank one.
M.E. Dudkin, O. Yu. Dyuzhenkova
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Multiparameter perturbation theory of matrices and linear operators [PDF]
Transactions of the American Mathematical Society, 2020 We show that a normal matrix A A with coefficients in C [ [ X ] ] \mathbb {C}[[X]] , X = ( X 1 , … , X n ) X=(X_1, \ldots , X_n) , can ...
Parusiński, Adam, Rond, Guillaume
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Global Perturbation of Nonlinear Eigenvalues
Advanced Nonlinear Studies, 2021 This paper generalizes the classical theory of perturbation of eigenvalues up to cover the most general setting where the operator surface 𝔏:[a,b]×[c,d]→Φ0(U,V){\mathfrak{L}:[a,b]\times[c,d]\to\Phi_{0}(U,V)}, (λ,μ)↦𝔏(λ,μ){(\lambda,\mu)\mapsto\mathfrak ...
López-Gómez Julián +1 more
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Cubo, 2021 The main goal of this work is to examine the periodic dynamic behavior of some retarded periodic partial differential equations (PDE). Taking into consideration that the linear part realizes the Hille-Yosida condition, we discuss the Massera’s problem to
Abdelhai Elazzouzi +2 more
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On the nonlinear perturbations of self-adjoint operators
Advances in Nonlinear Analysis, 2022 Using elements of the theory of linear operators in Hilbert spaces and monotonicity tools we obtain the existence and uniqueness results for a wide class of nonlinear problems driven by the equation Tx=N(x)Tx=N\left(x), where TT is a self-adjoint ...
Bełdziński Michał +2 more
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Spectral theory for structured perturbations of linear operators [PDF]
Journal of Spectral Theory, 2018 We characterize the spectrum (and its parts) of operators which can be represented as " G=A+BC“ for a "simpler" operator A and a structured perturbation
ENGEL, KLAUS JOCHEN OTTO, Adler, Martin
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The ChPT: top-down and bottom-up
Journal of High Energy Physics, 2021 In this work, higher-derivative corrections of the non-linear sigma model of both even and odd intrinsic-parity sectors are systematically studied, focusing on ordered amplitudes of flavor scalars in massless limit. It should correspond to a theory known
Karol Kampf
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Nonautonomous Dynamical Systems, 2022 In this work, we study the existence of periodic solutions for a class of linear partial functional differential equations with infinite delay. Inspiring by an existing study, by applying the perturbation theory of semi-Fredholm operators, we introduce a
Elazzouzi Abdelhai +2 more
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Nonlinear differential equations with perturbed Dirichlet integral boundary conditions
Boundary Value Problems, 2021 This paper is devoted to prove the existence of positive solutions of a second order differential equation with a nonhomogeneous Dirichlet conditions given by a parameter dependence integral.
Alberto Cabada, Javier Iglesias
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Open Mathematics, 2021 This work intends to treat the existence of mild solutions for the Hilfer fractional hybrid differential equation (HFHDE) with linear perturbation of first and second type in partially ordered Banach spaces. First, we establish the results concerning the
Gabeleh Moosa +3 more
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