Abstract:
We consider classes of elliptic equations of the form $F(x,u,\Delta u,D^2u)=0$ for the solutions of which one establishes local and global a priori estimates for $|D^2u|=(\sum_{ij}u^2_{x_ix_j})^{1/2}$ and $|D^3u|=(\sum_{ijk}u^2_{x_ix_jx_k})^{1/2}$. In particular, one investigates the Monge-Ampere equation $\det\|u_{x_ix_j}\|=f(x)$, $f(x)>0$ and for its convex solutions one constructs a local $|D^2u|$ and a global estimate for $\|D^3u\|_{L^2}$ and a local estimate for.