Concentration-compactness phenomena in the higher order Liouville's equation
arXiv:0809.2172 · doi:10.1016/j.jfa.2009.02.017
Abstract
We investigate different concentration-compactness phenomena related to the Q-curvature in arbitrary even dimension. We first treat the case of an open domain in , then that of a closed manifold and, finally, the particular case of the sphere . In all cases we allow the sign of the Q-curvature to vary, and show that in the case of a closed manifold, contrary to the case of open domains in , concentration phenomena can occur only at points of positive Q-curvature. As a consequence, on a locally conformally flat manifold of non-positive Euler characteristic we always have compactness.
26 pages, revised version