In this dissertation, we transform the equation in the upper half space first studied by Caffarelli and Silvestre to an equation in the Euclidean unit ball. We identify the Poisson kernel for the equation in the unit ball. Using the Poisson kernel, we define the extension operator. We prove an extension inequality in the limit case and identify the extremal functions using the method of moving spheres. In addition we offer an interpretation of the limit case inequality as a conformally invariant generalization of Carleman's inequality.
Read
