Some energy properties of Yang-Mills connections

E is a vector bundle over a compact Riemannian manifold M=Mn, n≥4, and A is a Yang-Mills connection with Ln2 curvature FA on E. Through a mean value inequality of the density |FA|n2, an energy concentrate principle of sequences of solutions that have bounded energy is proved. Unless E is a flat bundle, the energy must be bounded from below by some positive constant.