Mathematics · 2020 · 20 citations · 7 references
Natural SciencesComputational EngineeringComputational MechanicsDifferential EquationsTheoretical PhysicsBoundary-value ProblemsEigenvalue ProblemsOperator TheoryPerturbation MethodsPerturbation TheorySpectral AnalysisBoundary ProblemBoundary Value Eigenvalue ProblemsDirichlet ProblemsEigenvalue Boundary-value ProblemsElliptic Boundary-value ProblemsPerturbation Of Boundary Value ProblemsPerturbation Theory Of Operators
In this paper, the authors consider the construction of one class of perturbed problems to the Dirichlet problem for the elliptic equation. The operators of both problems are isospectral, which makes it possible to construct solutions to the perturbed problem using the Fourier method. This article focuses on the Dirichlet problem for the elliptic equation perturbed by the selected variable. We established the spectral properties of the perturbed operator. In this work, we found the eigenvalues and eigenfunctions of the perturbed task operator. Further, we proved the completeness, minimal spanning system, and Riesz basis system of eigenfunctions of the perturbed operator. Finally, we proved the theorem on the existence and uniqueness of the solution to the boundary value problem for a perturbed elliptic equation.
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