We study operators H and H(,0) acting on the Hilbert Space L('2)(R). The free or unperturbed operator H(,0) is the multiplication (also known as the position) operator x. We consider H = H(,0) + A, where the perturbation ...

In this thesis we consider the system of two unbounded single server queues in which a customer upon arrival joins both queues. The arrivals are assumed to form a Poisson process with mean interarrival time 1 and the servers ...

Difference equation techniques are applied to determine sufficient conditions on polynomials P(x,y) for which the Fischer space related differential equation.;(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI).;has (a) ...