this paper deals with the boundary value problem involving the differential equation ell y:=-y''+qy=lambda y, subject to the eigenparameter dependent boundary conditions along with the following discontinuity conditions y(d+0)=a y(d-0), y'(d+0)=ay'(d-0)+b y(d-0). in this problem q(x), d, a , b are real, qin l^2(0,pi), din(0,pi) and lambda is a parameter independent of x. by ...

We study a static massless minimally coupled scalar field created by a source in a static D-dimensional spacetime. We demonstrate that the corresponding equation for this field is invariant under a special transformation of the background metric. This transformation consists of the static conformal transformation of the spatial part of the metric accompanied by a properly chosen transformation ...

We review the notion of a gauge natural theory and we show in particular its role in implementing the very basic principles of any reasonable fundamental physical interaction. Conservation laws are investigated in this general framework by means of a skilful application of Nöther theorem together with the theory of superpotentials. Wess–Zumino model interacting with a gravitational fields is co...