Null mean curvature flow and outermost MOTS
arXiv:1503.04023 · doi:10.4310/jdg/1549422101
Abstract
We study the evolution of hypersurfaces in spacetime initial data sets by their null mean curvature. A theory of weak solutions is developed using the level-set approach. Starting from an arbitrary mean convex, outer untapped hypersurface , we show that there exists a weak solution to the null mean curvature flow, given as a limit of approximate solutions that are defined using the -regularization method. We show that the approximate solutions blow up on the outermost MOTS and the weak solution converges (as boundaries of finite perimeter sets) to a generalized MOTS.
A mistake in the use of the L^1 norm of the mean curvature instead of the L^2 norm in proofs of Theorems 37 and 39 was corrected. The use of the L^2 norm is needed in the application of the varifold convergence