Abstract
n this study we present a new approach for investigation of some
Sturm-Liouville systems with nonlocal boundary conditions. In the
theory of boundary value problems for two-order differential
equations the basic concepts and methods have been formulated
studying the problems of classical mathematical physics. However,
many modern problems, which arise as the mathematical modeling of
some systems and processes in the fields of physics, such as the
vibration of strings, the interaction of atomic particles motivate
to formulate and investigate the new ones, for example, a class of
Sturm-Liouville problems with nonlocal boundary conditions. Such
conditions arise when we cannot measure data directly at the
boundary. In this case, the problem is formulated, where the value
of the solution and its derivative is linked to interior points of
the considered interval. Sturm-Liouville problems together with
transmission conditions at some interior points is very important
for solving many problems of mathematical physics. In this study we
present a new approach for investigation of boundary value problems
consisting of the two interval Sturm-Liouville equations. This kind
of boundary value transmission problems are connected with various
physical transfer problems (for example, heat and mass transfer
problems). We define a new Hilbert space and linear differential
operator in it such a way that the considered nonlocal problem can
be interpreted as an spectral problem. We investigate the main
spectral properties of the problem under consideration. Particularly
we present a new criteria for Sturm-Comparison theorems. Our main
result generalizes the classical comparison theorem for regular
Sturm-Liouville problems.