Long time behaviors of Ricci flow and applications

In this thesis, we will first extend the pseudo-locality of the Ricci flow on compact Riemannian manifolds discovered by Perelman to complete noncompact Riemannian manifolds. Then, we will apply it to study the long time existence of the Kahler-Ricci flow on complete noncompact Kahler manifolds with reasonable geometric assumptions. Finally, we will give some examples of complete flat Kahler metrics on the complex projective space with some divisor deleted.