On one class eigenvalue problem with eigenvalue parameter in the boundary condition at one end-point (original) (raw)

Some properties of eigenvalues and generalized eigenvectors of one boundary-value problem

2016

We investigate a discontinuous boundary value problem which consists of a Sturm-Liouville equation with piecewise continuous potential together with eigenparameter dependent boundary conditions and supplementary transmission conditions. We establish some spectral properties of the considered problem. In particular, it is shown that the problem under consideration has precisely denumerable many eigenvalues λ 1 , λ 2 , ..., which are real and tends to +∞. Moreover, it is proven that the generalized eigenvectors form a Riesz basis of the adequate Hilbert space.

On the Principal Eigenvalues to Some Boundary Value Problems with Indefinite Weight

This paper deals with principal eigenvalues of the following class of boundary value problems −∆u = λa(x)u, x ∈ Ω, ∂u ∂n + f (x)u = 0, x ∈ ∂Ω, where Ω is a bounded region in R N with smooth boundary ∂Ω, a(x) and f (x) are indefinite weight functions which assumed to be continuous inΩ and ∂Ω, respectively, and at least one of them is not identically zero. We give a variational approach to find principal eigenvalues of this problem, and especially we find a necessary condition on f (x) to have principal eigenvalues. Our method extends those of Afrouzi and Brown (Proc. Amer. Math. Soc. 146 (1998)) in the sense that boundary condition in this paper is a continuous function of x.

Resolvent operator and spectrum of new type boundary value problems

Filomat, 2015

The aim of this study is to investigate a new type boundary value problems which consist of the equation -y''(x) + (By)(x) = ?y(x) on two disjoint intervals (-1,0) and (0,1) together with transmission conditions at the point of interaction x = 0 and with eigenparameter dependent boundary conditions, where B is an abstract linear operator, unbounded in general, in the direct sum of Lebesgue spaces L2(-1,0)( L2(0,1). By suggesting an own approaches we introduce modified Hilbert space and linear operator in it such a way that the considered problem can be interpreted as an eigenvalue problem of this operator. We establish such properties as isomorphism and coerciveness with respect to spectral parameter, maximal decreasing of the resolvent operator and discreteness of the spectrum. Further we examine asymptotic behaviour of the eigenvalues.

Dependence Of Eigenvalues Of Some Boundary Value Problems∗

2021

In this work we deal with a system of two first-order differential equations containing the same eigenvalue parameter. We consider some suitable separated real and complex coupled boundary conditions, and show that the eigenvalues generated by this system are continuous in an eigenvalue branch. Also we introduce the ordinary and Frechet derivatives of these eigenvalues with respect to some elements of the data.

A boundary value problem with a discontinuous coefficient and containing a spectral parameter in the boundary condition

International Journal of Mathematics and Mathematical Sciences, 1995

A singular non-self-adjoint boundary value problem is considered. This problem has a discontinuous coefficient with a spectral parameter in the boundary condition. Some solutions of the eigenvalue equation are given. The discrete spectrum is studied and the resolvent is obtained. Formulation of the adjoint problem is deduced and hence the continuous spectrum of the considered problem is given. Furthermore, the spectrum of the adjoint problem is investigated.

Qualitative analysis of eigenvalues and eigenfunctions of one boundary value-transmission problem

Boundary Value Problems, 2016

The aim of this study is to investigate various qualitative properties of eigenvalues and corresponding eigenfunctions of one Sturm-Liouville problem with an interior singular point. We introduce a new Hilbert space and integral operator in it such a way that the problem under consideration can be interpreted as a spectral problem of this operator. By using our own approaches we investigate such properties as uniform convergence of the eigenfunction expansions, the Parseval equality, the Rayleigh-Ritz formula, the minimax principle, and the monotonicity of eigenvalues for the considered boundary value-transmission problem (BVTP).

Elliptic Eigenvalue Problems with Eigenparameter Dependent Boundary Conditions

Journal of Differential Equations, 2001

hrynivÄ math.ucalgary.ca. 3 H.L. acknowledges support of the Fonds zur Fo rderung der wissenschaftlichen Forschung of Austria, Project P 12176 MAT. 4 B.N. initiated this project but unfortunately died before its completion. His research was supported by Ministry of Sciences of Croatia.

Characterization of the spectrum of irregular boundary value problem for the

2012

We consider the spectral problem generated by the Sturm-Liouville equation with an arbitrary complex-valued potential q(x) ∈ L 2 (0, π) and irregular boundary conditions. We establish necessary and sufficient conditions for a set of complex numbers to be the spectrum of such an operator. In the present paper, we consider the eigenvalue problem for the Sturm-Liouvulle equation u ′′ − q(x)u + λu = 0 (1) on the interval (0, π) with the boundary conditions u ′ (0) + (−1) θ u ′ (π) + bu(π) = 0, u(0) + (−1) θ+1 u(π) = 0, (2) where b is a complex number, θ = 0, 1, and the function q(x) is an arbitrary complex-valued function of the class L 2 (0, π). Denote by c(x, µ), s(x, µ) (λ = µ 2) the fundamental system of solutions to (1) with the initial conditions c(0, µ) = s ′ (0, µ) = 1, c ′ (0, µ) = s(0, µ) = 0. The following identity is well known c(x, µ)s ′ (x, µ) − c ′ (x, µ)s(x, µ) = 1. (3) Simple calculations show that the characteristic equation of (1), (2) can be reduced to the form ∆(µ) = 0, where