MATHEMATICA BOHEMICA, Vol. 139, No. 2, pp. 213-229, 2014

On discreteness of spectrum of a functional differential operator

Sergey Labovskiy, Mário Frengue Getimane

Sergey Labovskiy, Statistics and Informatics, Moscow State University of Economics, Nezhinskaya st. 7, 119501 Moscow, Russia, e-mail: labovski@gmail.com; Mário Frengue Getimane, Instituto Superior de Transportes e Comunicações, Prolong. da Av. Kim Il Sung (IFT/TDM) - Edificio D1 Caixa Postal, 2088 Maputo, Mozambique, e-mail: mgetimane@isutc.transcom.co.mz

Abstract: We study conditions of discreteness of spectrum of the functional-differential operator
\mathcal{L} u=-u"+p(x)u(x)+\int_{-\infty}^\infty(u(x)-u(s))  d_s r(x,s)
on $(-\infty,\infty)$. In the absence of the integral term this operator is a one-dimensional Schrodinger operator. In this paper we consider a symmetric operator with real spectrum. Conditions of discreteness are obtained in terms of the first eigenvalue of a truncated operator. We also obtain one simple condition for discreteness of spectrum.

Keywords: spectrum; functional differential operator

Classification (MSC 2010): 34K06, 34L05


Full text available as PDF.

Access to the full text of journal articles on this site is restricted to the subscribers of Myris Trade. To activate your access, please contact Myris Trade at myris@myris.cz.


[Previous Article] [Next Article] [Contents of This Number] [Contents of Mathematica Bohemica]
[Full text of the older issues of Mathematica Bohemica at DML-CZ]