Hausdorff measure and stability for the p-obstacle problem (2

In this paper we analyze the free boundary for the inhomogeneous obstacle problem with zero obstacle governed by the degenerate operator where f is a positive, Lipschitz function, and is of the p-Laplacian type, i.e., As a result of our analysis we obtain stability and finite (N−1)-Hausdorff measure of the free boundary. Our technique is a modified version of that of L.A. Caffarelli, who obtained similar results for p=2.