A new geometric flow with rotational invariance

In this paper we introduce a new geometric flow with rotational invariance and prove that, under this kind of flow, an arbitrary smooth closed contractible hypersurface in the Euclidean space Rn+1 (n, 1) converges to Sn in the C1-topology as t goes to the infinity. This result covers the well-known theorem of Gage and Hamilton in [4] for the curvature flow of plane curves and the famous result of Huisken in [5] on the flow by mean curvature of convex surfaces, respectively.