Energy in critical collapse

Abstract

We study the energy issue in critical collapse. It is found that in critical collapse, the contribution from the material energy is greater than that from the gravitational energy. The quantity m/r plays an important role in identifying the formation of apparent horizon in gravitational collapse, where m is the Misner-Sharp mass and r the areal radius. We observe that in critical collapse, the maximum value of m/r fluctuates between 2/15 and 4/15. This denotes a large gap between critical collapse and black hole formation for which the criterion is m/r=1/2.